Deputy Secretary of State John C. Whitehead said yesterday that "change is coming very fast" in the Soviet-dominated countries of Eastern Europe, and predicted that most of them are likely to be "a little less dependent on the Soviet Union" and "a little more oriented to the United States" by the end of the Reagan administration next January.

Whitehead, who returned Wednesday night from his fourth trip to the area, has been the administration's point man for Eastern Europe since mid-1986.

In an interview, the former Wall Street investment banker said Poland and Hungary are ready for new levels of cooperation with the United States, with those two countries improving their human rights performance and economic policies and the United States reciprocating with efforts to deal with their massive external debts and help integrate them into the global trading system.

In the Reagan administration until now, U.S. relations with Poland and Hungary, like those of other Eastern European nations, have been guided by a slow "step-by-step" program of individual actions by each side. Whitehead's remarks suggested that those two nations are ready for closer and broader relationships with the United States, but he declined to give details of how this might work.

Bulgaria, which is among the nations Whitehead visited during his just-completed trip, "may be the sleeper of Eastern Europe" in its potential for improved ties with Washington, he said.

Recent news reports from Sofia portrayed Bulgaria as among the most reluctant to distance itself from Moscow or to make major internal changes. However, Whitehead said Bulgarian President Todor Zhivkov is "much more receptive to human rights concerns than a year ago" and that his government has worked out "a very sensible plan to reform the economy."

On the minus side, Whitehead said Romanian President Nicolae Ceausescu "reacted badly" on being told that the chances for renewal of his country's most-favored-nation trade status later this year are "not very good" because of the human rights situation there. After his "disappointing" three-hour conversation with Ceausescu in Bucharest, Whitehead said, the chances for a continuation of Romania's trade benefits are "even less."

"There is no willingness to change their repression of their people, which is very severe," said Whitehead.

In general, he said, "the beginnings of dramatic change" are evident in the Eastern European countries.

Referring to policies propounded by Soviet leader Mikhail Gorbachev, Whitehead said, "All of these countries are watching the changes taking place in the Soviet Union, studying the concepts of glasnost {openness} and perestroika {restructuring} and rapidly developing their own concepts, each in his own way."

"Governments are moving toward democracy in some places. Their economies are moving toward market-oriented, western-style economies less controlled by government decisions. There is a greater sense of independence," he said.

The United States should encourage these trends, and "prospects are good" for additional improvements in relations with Washington, Whitehead said.