OF THE FEW world-class art dealers in Washington there is only one--Jem Hom is his name--who, before he started selling etchings by Picasso, made his living with his wok.

"To pay my way through school, I cooked," says Hom. "I worked in Manhattan, for the Golden Dragon, in Chinatown, on Mott Street. I worked for the Pacific, too, and also for the Dragon Seed. I started as a waiter, later chopped the vegetables, and then progressed to chef."

Hom may be the only print expert in town who, before he started selling Winslow Homers and Gauguins, peddled schlock art to hotels -- schlock art that he did not buy, but instead produced himself.

"It was hard work, and no fun," says Hom. "I remember how my heart sank when a trailer-load of plywood was unloaded at my door. I had promised to provide 400 pictures. I did impressionistic scenes of London, Paris, Venice, Rome, in half a dozen color schemes -- though I'd never seen those cities. I did still lifes, too, of apples, for $10 each. I had such a mental block I couldn't bear to start until the deadline neared. But I had to make a living. So I ground the pictures out."

In other ways as well, Hom is not like other dealers. He never shows the trendy. One cannot imagine him stooping to the hard sell, the glad hand or the hype. He is quiet, not flamboyant. He is just about at skillful at ping-pong and at basketball as he is at connoisseurship. He knew nothing about Western art -- had never even seen a European painting -- until he was 16.

Jem Hom, a decade ago, sold prints from his little frame shop in Bethesda. He later had a two-room gallery on the P Street Strip. The HomSee HOM, L12, Col. 1 HOM, From L1 Gallery now occupies a brick Victorian rowhouse at 2106 O St. NW. The walls are washed with daylight, the carpet is thick wool, an open central stair connects the first two floors. Occasionally the plate-glass door is opened by a stranger who asks the man behind the desk, "Did you make this stuff yourself." Jem Hom answers no, sir. But he does so without smiling, and with unshakable politeness. No one who knows classic prints would ask him such a question. Pictures of the sort he sells are rarely seen in stores.

The Hom Gallery specializes in late 19th- and early 20th-century graphics. His shows are small, but choice. They would not look out of place in the print rooms of museums. He has given one-man print shows to Henri Matisse, Toulouse-Lautrec, Pissarro, Louis Lozowick, Max Weber, Elie Nadelman, Thomas Hart Benton and John Sloan. Sometimes he displays art that's not for sale. Last fall he brought to Washington a scholarly exhibit full of Cruikshanks and Bonnards, Childe Hassams and Daumiers, called "Prints About Prints."

His current exhibition -- the first he's ever given to a printmaker from Washington -- is a retrospective of the etchings of Mark Leithauser. "I chose Leithauser," says Hom, "because his art is not ordinary." Leithauser is probably the best etcher in town.

The finest pictures in Hom's gallery may be the ones in drawers. Hom prefers to show these objects one by one: a rare monotype in color made by Georges Rouault (only three others are known); a nearly-Oriental lithograph in color by Toulouse-Lautrec; a Kathe Kollwitz etching dated 1909; "The Casting Office," a 1944 Raphael Soyer; two small oils by Maurice Prendergast; a 1905 Picasso. Ask his clients, his competitors, or the curators that Hom supplies: No print dealer in town boasts an inventory finer.

"Jem Hom," says art dealer Chris Middendorf, "is among the most important art dealers around. He sells nothing but class objects. He's sitting here in Washington, and -- save for the professionals -- almost no one knows he's here."

"Hom," says Andrew Robison, curator of prints and drawings at the National Gallery of Art, "is a careful, studious dealer, among the best of the younger generation. He tries to handle excellent things. Recently we purchased one of his Pissarros."

"I hold Jem Hom in the highest regard," says Alan Fern of the Library of Congress. "Also, I like him. What I admire most about him is his combination of adventurousness, his willingness to go into areas that aren't fashionable and his insistence on high quality. His approach to prints is scholarly, but it is never dry. Frequently I hear, or read, of a print I'd love to see. Next thing you know, it shows up on his wall."

"Jem is marvelous," says dealer Harry Lunn. "He is one of the least visible, and most successful, art dealers in town. He's carved out a specialty. He has fine relationships with the print people who count in New York, Paris, London. And ethically he's impeccable."

Next June, the Smithsonian Institution's Exhibition Service will begin to circulate the Steven Block collection of the late 19th-century lithographs of James McNeil Whistler. The exhibit will include 82 impressions. Eighty of the 82 were bought by Block from Hom.

Block, who works in Washington, is a government employe. "When I walked into Jem's gallery in November 1978, I'd never bought a print. I started to buy one Nadelman -- and ended up with 10. Then somehow he acquired those extraordinary Whistlers." (Hom purchased them in England, but will not say where.) "I know what he paid," says Block. "He does not overcharge. If five years ago you'd told me that the Block Collection would be going out on tour, I would not have believed you. I owe a lot to Hom."

"So do I," says Middendorf. "When I started selling art here, Jem Hom was my mentor. He'd take me to New York so that I could meet the dealers and evaluate their inventories. His memory is amazing. So is his knowledge of the players. He knows just what sellers own, and just what buyers want. Once, when we were visiting a dealer in Manhattan, Jem saw a print he liked. He bought it on the spot for $600, but didn't own it long. Fifteen minutes later he'd sold it to another dealer -- for $1,600. His expenses were $2 -- for cab fare. His profit was $1,000."

Hom is 45. He speaks tersely, and with caution. When asked about his life, he answers direct questions, but does not volunteer.

"I was born in Canton, China. I spent my childhood near there in a little farming village. When I was two, my father traveled to America, to run a restaurant in Richmond. Because he sent us dollars, we were better off than most. I remember running through the countryside and seeing lookouts posted everywhere. They were watching for the Japanese. I remember hiding when the Japanese came down from the mountains to take the animals away. In 1945, I started boarding school in Canton. In 1948, my family left town as Mao's army marched in.

"First we went to Hong Kong. We stayed with mother's relatives. Not long ago I saw a poster in Bethesda for a midnight showing of Chinese kung fu movies. One name on the ad struck me as familiar -- I think you'd spell it 'Chen Tak Fou.' I thought it must be him. It was. He's a cousin of my mother's. Twenty years ago he was a kung fu master. He is a kung fu master still.

"In 1952, when I was 16, we moved from Hong Kong straight to Richmond. Though I knew no English, I entered junior high school. I did okay in math. My ignorance may have helped me. I developed rather quickly a sort of photographic memory. Though I couldn't read the words, I could visualize whole sentences. I could memorize a map. I had seen my first van Goghs, and thought I'd be a painter. By then I'd come to love works of Western art.

"My grandfather, my father's father, collected Chinese objects, mostly porcelains and bronzes. But I paid no attention to the Chinese art at home. Compared to Western art, Chinese art seemed dull to me. It never seemed to change.

"I started college in Virginia, at Richmond Professional Institute, and then, in my senior year, transferred to New York, to the Parsons School of Design. Half my money came from cooking then; the other half from painting. I finished school in 1960, and got married the same year. It was in those days that I painted portraits on commission, murals for small restaurants and still lifes for hotels. Not all my art was schlock. In 1961, Henri of the Henri Gallery, it was then in Alexandria, gave me a small show. But the schlock art paid the bills, and the schlock art got me down.

"In 1964, we thought of moving West, but on the way to California stopped a while in Washington. My wife, Betty, a biochemist, heard about a job at the National Institutes of Health and was hired on the spot. We settled in Bethesda. That's where I opened the Hom Gallery in the old Leland Street Shopping Center -- it was primarily a frame shop then -- in 1964.

"I already owned some prints. In New York, in the '50s, you could buy very nice things for very little money. I bought as many as I could. I filled the walls with Homs -- and with prints by Thomas Benton and Milton Avery. That's how I began.

"I sold American prints at first. They were greatly undervalued then. I'd go to New York to the Kennedy Galleries and buy 100 Martin Lewis prints for $40 each. Then I'd sell them in Bethesda. Then I started branching out. I'd pay $300 for a poster by Toulouse-Lautrec; I bought lithographs by Pierre Bonnard and the least expensive etchings of Matisse. Because I knew how to make frames, I always made a living. But I hated making frames as much as I hated painting for hotels. And as soon as I could, I stopped. We lived very modestly. I saved until I could begin buying prints in volume.

"In 1966 I went to Europe for the first time. Now I fly to Paris or to London perhaps six times a year. At first I knew nothing about prints. Now I know a bit. I'd read catalogues and books, of course, but you know nothing about prints until you see the real thing. I can tell at once if an old print has been washed. I think by now that I can tell a good print from a bad one. That's why I show Leithauser. I also sell the carvings of sculptor Leonard Cave. I admire him tremendously. There are a lot of so-called artists working in this area. But to find a good one is not easy.

"I keep my operation small. I take no money from investors. When you buy pictures with your own cash, you'd best be sure you're right. I don't believe in trendy art -- have to trust in quality. Washington's collectors are far more knowledgeable today than they were 10 years ago, and I think that has helped me. Perhaps a third of my sales now are to Washington collectors; I also like to sell to local art museums. You either show the art you love or you run a store. What makes my work a pleasure is that I deal in things I like."