The house was decorated with ballons and colorful paper streamers. The guests, mostly Vietnamese, wore summer-weight party silks more suited to the warmth of Southeast than snowy suburban Maryland.

They were gathering for a South Vietnamese -style Buddhist wedding, a ceremony in which parents, not priests, play the most important roles. This one would be special, because both sets of parents had been left behind in South Vietnam when the Thieu government collapsed under communist pressure in 1975.

The wedding of 19-year-old Kim Phuon Thi Le, the bride, and Thanh Duy Ho, 25, the groom, was to be as reminiscent of South Vietnam as the couple and their relatives could make it, in part as a gesture to the parents who could not be present.

Just as important, they said, it was to be as close to the real event as possible in tribute to their American friends who had helped them adjust to their new country.

The marriage Saturday of Kim and Thanh was held before an ancestral altar at the Rockville home of Kum Phuong's aunt and uncle. As the bride and groom executed the ancient ritual roles, Vietnamese and American friends and family stood around them, coaching, chattering excitedly, and whispering interpretations of the ritual.

The two met last year at a party here.

Five years ago Thanh arrived in Philadelphia to study Englis. He spent two years at George Washington University and one year at Villanova University. When Saigon fell in May, 1975, he was stranded here, because the rest of his immediate family was unable to flee Vietnam and their tuition money to him stopped. He quit school and began driving a taxi in northern Virginia.

Kim Phuong, her sister Kim Loan Le and Kim Loan's two children, escaped Saigon the day before the fall of their country. Kim Loan, who worked for the Americans there, had previously arranged the trip. Unfortunately, her husband, who planned to leave with them, never got out.

At her sister's wedding, Kim Loan, forcing a smile for a visitor, said "I do not know what happenen to him. I hear he's in a (military) reducation camp."

The women and the two children were resettled in this country by Josephine Steinman, their cousin from Vietnam, and her husband, Ron, the Washington producer of NBC's Today Show. Altogether, the Steinman's took in 16 of Josephine's relatives who fled Vietnam, including her parents.

Now, a year and a half later, the adults have jobs, the children are in-school and the families are living in their own homes.

Josephine, the supervisor of the Buddhist ritual, discovered she had to go all the way to Chinatown in New York City to purchase some of the necessary items for the wedding altar. Even then it wasn't easy, she said. They found the Chinese wedding scrolls in the red and gold marriage colors and a particular size of incense stick, but they never located the traditional suckling pig.

At the outset of the ceremony, Thanh, wearing ornate blue and silver silk and surrounded by 20 relatives, walked a block to the house where his bride was sequestered. His uncle, Khiet Tran-Kiem of Philadelphia, the eldest representative of Thanh's family, knocked on the door and asked permission to enter.

The bride's aunt and uncle, Mr. and Mrs. Phat Hong Tu, Josephine Steinman's parents, consented and the groom's party entered.

Then followed a series of gift exchanges between the aunt and uncles - jewelry and wine, several trays of traditional gifts, and ultimately, and agreement to the nuptial match.

Eventually, the bride, doll-like in the red, gold and yellow silks of the Vietnamese bride, quietly entered the room. She carried pink and white carnations and around her neck hung thin chains of gold with a clasp sympolizing longevity, happiness and prosperity.

The altar candles and incense were lit and placed between flowers. The couple, traditional wedding hats on their heads, knelt and then bowed before the altar, offering prayers to their families. At last they stood, faced each other and without words, and exchanged rings.

"In the eyes of the family they are married," a friend explained. The necessary U.S. legal ceremony would follow later before a justice of the peace.

There were some tears of happiness and some of sadness as the families recalled their trials in the past year and a half. As for the absent relatives, Thanh said he learned in a letter from his grandmother in Saigon that his family needs medicines and that his father, a military officer, had been sent off to a reeducation camp.

Kim Phuong's father, a dentist, is practicing his profession again, she was informed by relattives in France. Her parents live in Saigon.