China's Communist Party named 91 new members to its Central Committee today in what amounted to a further political victory for the party's reformist group, headed by the country's top leader, Deng Xiaoping.

Most of the 56 officials appointed to full membership in the Central Committee appeared to owe their positions to the reformist group and its policies. The Central Committee now has 210 members and 133 alternate members.

The announcement of the new appointments to the Central Committee, made by the official New China News Agency, came six days after the party announced a major shake-up in the Politburo, with 10 of 24 members resigning. That move pointed to a substantial consolidation of power for Deng and his chosen successors. At the same time, 64 elderly members of the Central Committee submitted resignations, providing most of the vacancies that were filled today.

According to the news agency, the average age of those promoted to the Central Committee as full and alternate members is 50.1, and 76 percent of them have some college education. The old membership of the Central Committee had an average age of more than 60.

The Central Committee functions as a kind of parliament of the party, and its members hold top positions in the party and government.

"All the indications are that once again, Deng has done what he wanted," a diplomat here said of the new appointments.

The largest block of persons promoted to the Central Committee was 22 governors or provincial party secretaries who had been appointed to those positions during the past six months. Also elevated were 14 recently appointed government ministers.

The Central Committee appointments announced today seemed to point to a further depoliticizing of China's military. More than 20 senior military officers resigned from full membership in the Central Committee, according to one account. A check of the backgrounds of the new appointees indicated that perhaps only 11 held military positions.

The military gained what many Chinese considered to be disproportionate representation in the Politburo and Central Committee during the Cultural Revolution of 1966-76.

There is no constitutional requirement that the military be represented in these party bodies. But the military long has been a key element in the balance of power, and the size of its representation in party bodies is seen by some observers as an important measure of its political influence.

Meanwhile, an unforeseen development that might worry the party leaders has been the appearance on the Peking University campus in recent days of posters that call for increased freedom of speech and greater democracy in order to achieve modernization.

It was the first time in five years that students have made such an appeal. They did so cautiously, within the context of protests against what they described as signs of a revival of Japanese militarism and a Chinese policy toward Japan that they consider too conciliatory.

Most of the more than 200 posters appearing at the country's most prestigious university dealt with the issue of Japan. Many of them seemed to support party policies. But a number made explicit references to a need for democracy.

One, for example, dated Sept. 20, said that "in the battle between democracy and dictatorship at Peking University, dictatorship has won. But this is not yet the end. It is now time to hold a burial service for dictatorship." Another said, "In the restoration of the great Chinese nation, there must be democracy." It ended with the English words: "Long live democracy."

Several of the posters referred to an article in China's constitution that states that citizens "enjoy freedom of speech, of the press, of assembly, of association, of procession and of demonstration."