As if he didn't have enough to worry about with the Washington Star International Tennis Tournament fast approaching, tournament co-director John A. Harris has a new job.

Harris, 41, a lifetime Washington-area resident who presently lives in Potomac, was recently elected to the nine-man Men's International Professional Tennis Council (MIPTC), which rules men's pro tennis. And while his appointment does not become effective until Aug. 1, Harris is "doing a lot of thinking about it."

"I've already set up a whole set of files," said Harris, a five time contestant in the U.S. open. "There's not a whole lot I can do about it. I'm just getting prepared."

Harris also is busy with preparations for the Star tournament, which is played July 16-25 at the Washington Tennis Stadium at 16th and Kennedy Streets NW. In addition to trying to attract the best possible field for the $125,000 tournament, Harris must worry about keeping the fans and players happy and wanting to return.

"With the tournament, my life gets very hectic. This summer has gotten even worse," Harris said. "I enjoy it and look forward to it. It's changed my way of life. Starting in July, I spend all my time on the tournament."

"It's a matter of maybe a month. Fortunately, I can go out to the tournament and see him," said Harris's wife Nancy. "He's under a great deal of pressure and his hours are very long, but that's part of the job. Every June through July, we make very few plans. He works many nights and weekends."

Harris said he tries to bring his work home with him at night so he can have dinner with the family. The Harris' also like to escape with their children - Brian, 8, and Nicole, 6 - for a couple weeks in August to Park City, Utah, though this year's trip is in jeopardy because of his MIPTC appointment.

Harris receives no personal remuneration for his work on the Star tournament. (He also will not be paid for his MIPTC work).

"The whole purpose of the Star tennis is to raise money to put back into junior tennis," said Harris, who played for the University of Michigan's 1957 NCAA tennis champs. "That makes a direct cntribution to my community. That has always been the motivating factor for Donald Dell (the other co-director) and me.

All proceeds from the Star tournament go to the Washington Area Tennis Patrons Foundation (WATPF) of which Harris is executive secretary. The Foundation in turn funds the National Junior Tennis League, which operates junior tennis programs at 50 sites in Washington, Prince George's County, and Alexandria, Va; D.C. Department of Recreation clinics; and the 26-tournament Junior Grand Prix during the winter. Among its other activities, the foundation provides travelling expenses for area youths who qualify for Middle Atlantic Lawn Tennis Association events.

The foundation's receipts for 1976 were approximately $161,000, 62 per cent of ywhich were from the Star tournament, Harris said.

Since Dell and Harris started the tournament in 1969, the tennis facility at 16th and Kennedy has grown from 992 seats to 5,700 and a clubhouse and pro shop have also been built. While the stadium belongs to the United States Park Service, the improvements and much of the maintenance are funded by the foundation, Harris said.

Dell and Harris became friends nearly 30 years ago in Bethesda as both were learning to play tennis. The rivalry continued for many years as both played in tournaments along the East Coast.Dell became better-known as a player and was captain of the U.S. Davis Cup team.

But Dell said Harris is "the leading tournament director in this country.

"It really takes someone who loves tennis, someone who will devote the time. He's very creative. A lot of the summer tournaments that follow our Star tournament copy things," said Dell, who is the senior partner of Dell, Craighill, Fentress and Benton, a sports law firm which acts as general counsel to the Tennis Players Association.

Dell emphasized Harris does most of the work on the Star tournament. "I've got the greatest job in the world," Dell said. "I show up for the functions and he does all the work."

To make a living, Harris heads the Potomac Ventures, Inc., a firm which manages office and commercial space. He also has served as a consultant for the Charles E. Smith Company, a real estate developer, for the building of the Skyline Racquet and Health Club at Baileys Crossroads, Va., which will be the largest indoor recreational facility in the Washington area.

Harris will serve as vice president of the facility, which opens Oct. 1.

Harris' major goal on the MIPTC will be to see the tennis tour run in a more business-like manner, including better marketing, he said. The council meets for two or three days every six weeks in different parts of the world and, while Harris gets reimbursed for his travel, he must work the trips into his already crowded schedule.

"Maybe I'll just have to use my time a little more effectively," Harris said.