Marion Tucker an apartment dweller who lives with her elderly mother on Massachusetts Avenue near downtown Washington, does not want her neighborhood overrun with tourists so she went to city hall recently to tell officials emphatically how she feels.

"I don't want a hotel environment," she declared, adding that she doesn't want to "dodge my way through the tourists or through the rowdy and misbehaved children."

John Simpson, an executive in a corporation that owns a potentially lucrative 4,500-square-foot lot on the south side of Massachusetts Avenue between Fourth and Fifth streets NW, says he hopes to erect a 300-room hotel attached to an office building. The cost is estimated at $16 million.

He, too, went to city hall hoping to convince the same officials that they should alter the city's rigid zoning code to make it possible.

Tucker and Simpson were among dozens of witnesses -- investors, planners, lawyers, apartment tenants and civic activists -- who testified at a series of six hearings on a proposal by the city's planning office to transform a seedy mile-long stretch of Massachusetts Avenue into an enclave of hotels, apartment houses and office buildings.

The hearings by the D.C. Zoning Commision ended Monday, with commission Vice Chairman Walter E. Lewis indicating a decision may come early next year.

The proposal, spurred by the scheduled opening in 1983 of the city's $100 million convention center, calls for creating a new "hotel incentive zone" by letting builders erect bulkier and taller structures than the zoning code now permits if they include significant numbers of hotel accommodations or dwelling units. A map to be adopted separately would pinpoint the potential hotel locations.

Predictably, the proposal sparked controversy. The business community embraced it, although the hotel industry's trade association complained that it would not help existing hotels outside the proposed zone expand to meet the growing market. Individual citizens and spokesmen for civic groups condemned the proposal with near unanimity and demanded instead that virtually all the affected land be set aside to provide sites for housing units for local residents.

Apartments "can't possibly compete for the same sites as hotels because their profits are going to be that much less, and it's really almost fraudulent to contend that any housing is going to result from this [hotel zoning]," Jay Clark, chairman of the center-city Ward 2 Tenants Council, testified. The group has 300 individual and organizational members.

As proposed, the hotel zone would cover a mile-long sawtooth-edged strip of land roughly three blocks wide flanking Massachusetts Avenue from North Capitol Street, at the edge of Union Station Plaza and the Capitol grounds, northwestward almost to 14th Street NW.

Once among Washington's grandest avenues, much of Massachusetts Avenue now contains a motley collection of down-at-the-heels rooming houses, stores and parking lots. Midway along the route is the city's boarded-up old main library on weed-covered Mount Vernon Square, slated for renovation and use by the University of the District of Columbia. The convention center, fronting on New York Avenue between Ninth and 11th streets, is at the south edge of the proposed hotel zone.

City planning officials say the city must produce at least 3,000 new hotel rooms by the mid-1980s to serve conventioneers and that ideally many of these should be built within walking distance of the convention center.

James O. Gibson, the city's planning director, said the new zone would form a buffer and boundary between the downtown area and the Shaw residential neighborhood north of Massachusetts Avenue. Alfredo D. Echeverria, head of the office that drafted the plan, said fewer than 1,200 dwellng units now exist in the proposed hotel zone and that the plan contemplates keeping at least 800 of these.

Under existing commercial and special-purpose zoning in most of the area, virtually all of the 88 acres in the proposed zone could be developed as office buildings, Echeverria said.

To encourage hotel and high-rise residential development generally viewed as less lucrative to builders than office buildings, the planners propose to give builders the right to erect such buildings with roughly one-third more floor space than the present zoning code permits.

They also would lift building height restrictions in the area and let structures rise as tall as permitted by the congressionally enacted 1910 building-height law. That would permit some structures as high as 130 feet, 40 feet more than the present zoning limit. The higher roofs would have a stepped-back design to give the appearance of a lower skyline.

Clark, the tenant leader, disputed the need for the zoning bonuses to builders. "Rather than stimulating new housing, the proposed zone threatens existing residences," he said. "The ripple effect has kind of already started."