How do you form a Communist Party in a country where there are so few Communists?" a long-time foreign resident of Ethiopia asked.

"From the top down," he said, answering his own question, "because the leadership cannot trust anybody else."

The Marxist military government of Ethiopia last year began the laborious process of establishing a Communist Party in a country that, during centuries of feudalism, had no tradition of political parties, let alone Marxism. Much to the unhappiness of Ethiopia's Soviet friends, the goal still seems a long way off.

A body with the unwieldy name of the Commission for Organizing the Party of the Working People of Ethiopia was formed. Last month it held its third regular plenary session, but little progress toward forming a party was discerned.

Nevertheless, the commission serves a useful purpose for Ethiopia's leader, Chairman Mengistu Haile-Mariam, who chose the six other military men on its Exectuve Committee, which he heads.

The commission appears to be gradually replacing the Provisional Military Administrative Council, known as the Dergue, as the supreme governmental institution. The top leadership of the two groups is the same but since the 97-person Central Committee of the commission is predominantly civilian, it gives the impression that the government is moving toward establishing civilian rule.

To lend credibility to this possibility, all the members of the commission's Executive Committee have dropped their military titles, except for the defense minister, Gen. Tesfaye Gebrekidan, who is believed to rank fourth in the leadership. All are still in the Dergue, however.

Mengistu appears much more frequently now in business suits rather than in the camouflage military outfit he wore at the beginning of the revolution.

The other members of the commission's leadership, in apparent order of importance, are: Fikre Selassie, secretary general; Fisseha Desta, his deputy; Berhanu Bayih, in charge of foreign affairs; Legessie Asfaw, in charge of political organizations, and Teka Tulu, who is head of security.

How much influence the other six exert over Mengistu is the subject of intense debate since little information about their sessions becomes public. There is no doubt, however, that Mengistu is number one, since he selected the others, and few doubt that his word is final.

Fisseha and Berhanu went to Western Europe earlier this year in an effort to improve relations and gain aid, but Fisseha was also instrumental in forging the controversial alliance between Ethiopia and Libya.

Some analysts regard Legessie as the Soviet Union's man on the committee. Others doubt it.

One theory is that Mengistu is moving slowly on forming a party because he is first and foremost an Ethiopian nationalist and thus does not trust Soviet intentions.

A well-established Communist Party in Ethiopia could provide the Soviets with channels of influence outside the military. East Bloc diplomats have been heard to complain about the snail's pace of movement in forming a party and have talked about their desire for party-to-party relations as is common in Eastern Europe.

The lack of a party also causes problems in efforts to carry out Marxist policies.

Because of decades of U.S. influence, most of the senior civil servants are Western-educated and many do not agree with the policies. Although it is difficult to find any evidence that such officials have worked against Marxist policies, sometimes lack of action has the effect of blocking them.

A number of officials when interviewed were asked when they had become Marxists. The answer was invariably the same: a nervous laugh and a quick change of subject.

Many officials with Marxist sympathies also were educated in the United States. A number of Ethiopians came up with the explanation: "If you want to train a Marxist, send him to America. If you want to train a bourgeois conservative, send him to the Soviet Union."

Many analysts believe that it is only at the top levels of the commission that there are dedicated Marxists, although one leftist intellectual called them "half-baked, but sincere Marxists."

The commission is actively pursuing an anticorruption drive. So far the campaign has been long on Marxist organization and short on results.

Last month a proclamation was issued to establish a "working people's control committee" with wide powers, including detention, to carry out the anticorruption campaign.

The general belief is that Mengistu will use the drive to shake up some of the Dergue leadership where there have been rumors of corruption. Nobody, however, points a finger at Mengistu.

There were some telling graffiti on anticorruption posters put up in September at the beginning of the campaign.

The posters said: "His salary is 500 birr $250 a month. He squanders 200 birr a day. He received a 10,000 birr bank loan but he has built a house worth 70,000 birr. Who is this person?"

The answer was soon scrawled on many of the posters: "A member of the Dergue."

The posters were quickly removed.