The giant corporations that own the Sheraton Washington Hotel won an apparent victory over the hotel's residential neighbors yesterday in a decade-long dispute over the amount of off-street parking required to serve hotel guests and visitors.

After two hours of spirited debate, the D.C. Board of Zoning Adjustment agreed that the hotel at 2660 Woodley Rd. NW had failed to provide 898 parking spaces that were once made a condition for its expansion -- but that it now needs to provide a smaller number, perhaps around 650. The precise number will depend on a future recomputation BZA ordered of zoning requirements.

The parking dispute has pitted several hundred homeowners of Woodley Park, a neighborhood chiefly of row houses, against the corporate owners of the 60-year-old landmark hotel -- the Sheraton Corp., a subsidiary of the International Telephone & Telegraph conglomerate, and the John Hancock Mutual Life Insurance Co.

Residents have complained that hotel guests and an increased number of visitors to the hotel's enlarged convention facilities have inundated the neighborhood with a spillover of cars that block driveways and alleys and infringe on their life styles.

Although yesterday's ruling would require more than the 595 garage spaces now located on the hotel's 12-acre site, Sheraton attorney Whayne S. Quin said after the BZA's 4-to-1 vote that there already are enough surface spaces available to meet the moderately increased requirements. He said the hotel has a total of "something like 740" spaces.

William H. Carroll, chairman of a Woodley Park citizen's coalition, denounced the BZA vote, saying the increased number of spaces "is a pittance, not worth providing." Although the citizens seemed to win one point of principle in yesterday's vote -- that the city zoning administrator wrongly reduced the number of parking spaces the hotel must provide -- Carroll described that as meaningless.

Carroll predicted that the neighborhood would appeal the decision to the D.C. Court of Appeals, but that it would have trouble raising funds to combat the ample legal resources of the Sheraton's owners. Two door-to-door fund solicitations and a block party have raised $12,000 toward legal fees, Carroll said, and a sizable balance is still due.

The four BZA members who formed the majority in yesterday's vote all had critical things to say about the Sheraton and its management, but in the end they relied on legal precedents and technicalities in reaching their decision. It was based strictly on an arithmetical computation of the number of hotel-related parking spaces required tby the city's 1958 zoning code. The board decided that the hotel's convention facilities, while more than trebled in size by the recent $50 million reconstruction, is still incidental to hotel operations and requires no separate parking space of its own.

Sheraton's owners "had filthy hands" in initially promising 898 spaces and not ultimately delivering, said board member Walter E. Lewis. They would "make these general and glorious promises, orally" and then become vague in putting them in writing, said BZA chairman Connie Fortune.

Only Leonard L. McCants, a former BZA chairman who returned to the panel yesterday because he had participated in four hearings on the issue, supported Sheraton without reservation.