Encouraged by Zaire's decision to renew diplomatic relations, Israel plans to intensify its effort to restore ties with some of the other nearly two dozen black African countries that severed relations at the outset of the 1973 Middle East war, Israeli officials said today.

A Zairian envoy is scheduled to meet with Israeli Prime Minister Menachem Begin and Foreign Minister Yitzhak Shamir Sunday to convey formally the decision, which represents a breakthrough in Israel's effort to end its diplomatic isolation from black African states.

An Israeli Foreign Ministry spokesman called the decision, which Zairian President Mobutu Sese Seko announced in Kinshasa last night, an "important development" in Israeli-African relations. He added, "Israel calls on other countries of the continent to follow Zaire's example and renew their links of friendship and cooperation to the benefit of all parties."

Earlier in the week, Mobutu was reported to have decided to reject all U.S. aid as a result of a House committee's charges of corruption in his government and a vote to reduce aid to it. The official Zairian news agency was quoted as complaining that a vote Zaire had cast in favor of Israel at the United Nations, at the behest of the United States, "has not brought us very good fortune." In view of the new ties, this dissatisfaction seemed aimed only at the United States.

Before 1973, Israel was one of the most politically active foreign countries on the continent, maintaining formal relations with 22 black African states. The Africans long before had accepted the Jewish state as a small developing country that itself had struggled against British colonialism.

Israel trained African armies, developed African farmland and brought 8,000 Africans to Israel to study medicine, agriculture and engineering.

But with the onset of the 1973 war, most black African countries broke ties with Israel on the ground that it illegally occupied territory of Egypt, a member of the Organization of African Unity. Zaire was the first to make the break.

Israel now has relations with only three black African countries--Malawi, Swaziland and Lesotho--but Israeli development companies are active in at least 12, ranging from Kenya in the east to Nigeria in the west.

Israeli trade with black Africa exceeds $100 million annually, or three times the pre-1973 level, and the state-backed Agridev Co. has many projects throughout the continent. The Solel Boneh construction company has contracts totaling nearly $2 billion in black Africa, and an Israeli community of 500 families lives in Nigeria.

Moreover, the Israeli government maintains special-interest sections in foreign embassies in Zaire, Gabon, the Ivory Coast, Ghana and Kenya, and special trade representatives frequently travel to other states. The two other countries on the continent with which Israel has formal ties are South Africa and Egypt.

During the past two years, Israeli diplomacy has been intense in an effort to renew relations in black Africa, with Foreign Ministry Director-General David Kimche making several visits to talk with African leaders. Kimche had wide experience in Africa while serving with the Mossad, Israel's intelligence agency.

In November, Defense Minister Ariel Sharon toured several African capitals, including Kinshasa, and signed some contracts for arms sales and economic development, giving rise to speculation of imminent restoration of ties to Israel. However, the Israeli government's decision to annex the Golan Heights in December apparently caused some countries to postpone consideration of ties.

Late last year, Mobutu announced he was prepared to resume ties to Israel but not until other black African nations took a stand. Israeli sources said today that Mobutu apparently had given up his bid for a joint announcement.

"If other black African states had wanted to do it immediately, they probably would have done it with Zaire," an Israeli official said tonight. "But we think now that Zaire has done it, the others will have more courage. The taboo has been lifted."

Another question mark is the reaction of rejectionist Arab states. While a desire to maintain Third World solidarity was one factor in the 1973 severing of ties, an important incentive was a fear of Arab retaliation in the form of economic sanctions, coupled with promises of financial support should the Africans comply. Some black African countries have expressed disappointment at the amount of subsequent Arab aid.