The D.C. Zoning Commission is pressing the developer of the Tregaron estate to disclose the names of all the firm's principal owners before commission members decide whether to approve a zoning change to allow construction of 120 luxury town houses on the wooded 20-acre site in Northwest Washington.

Commission Chairman Walter Lewis has set a Nov. 30 deadline for the disclosure, according to commission secretary Cecil Tucker. Tucker said the commission is expected to vote Jan. 10 on the developer's request for a zoning change for a planned unit development.

Opponents of the project contend that the developer, Tregaron Development Corporation, is a front for an Israel-based international businessman, Shaul N. Eisenberg, who acquired a major interest in the development last year through a corporation he set up in the Netherlands Antilles called Catopale Investments, N.V.

The Washington Post recently reported Eisenberg's involvement in the project, but officials of the development firm have not confirmed it. Alan R. Novak, a general partner in the development, said recently: "My feeling is that disclosure of individual partners is for the partners to do, not for me."

Gary J. Kopff, a leader of a neighborhood group fighting the town house project and a vice president of the Federal National Mortgage Association (Fannie Mae), told the zoning commission last week that Catopale Investments put up practically all the capital for the venture and is the "effective owner" of the property.

Kopff cited documents filed with the D.C. Recorder of Deeds in January 1981 showing that Catopale holds a 37.5 percent interest in a limited partnership with the local developer, with an option to acquire up to 62.5 percent interest. Catopale also put up nearly all of the start-up capital, according to the documents.

"The Tregaron Development Corporation and its officers and consultants appear to be merely fronting for the real interests, with no equity at risk of their own, as they protect the offshore investors from legal liability and public disclosure," Kopff testified.

"This zoning commission has the right to ask who is the developer with the experience and financial capacity to deliver on this plan," he said.

A source close to the developer said that although Catopale has pumped "many millions of dollars" into the project, it has remained a "passive partner," content to leave most decision-making to Novak.

Catherine Armington, a senior research analyst with the Brookings Institution, testified last week that the proposed development would generate only $73,000 in additional tax revenue for the city annually, rather than the $1.8 million net increase projected by the developer.

"Many owners of nearby property believe that the relatively high density proposed for this planned unit development will reduce not only the special appeal of the neighborhood, but also the market value of the surrounding property," Armington said.

E. David Harrison, the local developer's general counsel and chief spokesman, said his firm relied on professional consultants for its estimates.

"I found it difficult at times to agree with Armington ," Harrison said.

Tregaron, the last major undeveloped tract in Northwest Washington and a designated historical landmark, was sold in late 1980 for $4.6 million by the heirs of Joseph E. Davies, a wealthy Washington lawyer. The Washington International School acquired the estate's Georgian-style mansion and about six acres of land. The remainder was purchased by the developers.