UNITED NATIONS (AP) _ The General Assembly on Tuesday passed its annual series of resolutions condemning South Africa's apartheid policy and called for a ''world conference on sanctions against racist South Africa.''

Nine resolutions were passed by a large majority of non-aligned and communist nations, with Western members voting against or abstaining on some of the measures.

The United States voted against six, abstained on two and favored one.

The basic resolution, adopted by a vote of 122-18 with 14 abstentions, asks all nations to impose sanctions, including a trade ban, oil supply boycott and prohibition of loans and investments.

It condemns ''policies of 'constructive engagement' and active collaboration with the apartheid regime followed by governments of certain Western and other states which give encouragement to the racist regime.''

''Constructive engagement'' is the phrase used by the Reagan administration for its policy toward South Africa's white-minority government. It opposes mandatory sanctions.

U.S. delegate Patrica Byrne said the U.S. policy has improved the lives of many black South Africans and was ''condemned unjustly.''

The General Assembly call for sanctions is not binding and has been largely ignored. Only the Security Council can impose mandatory sanctions, and council resolutions for such sanctions have been vetoed by the United States and Britain. The five permanent members of the council have the veto power.

Under a new resolution in the South African package, the General Assembly will organize, in cooperation with the Organization of African Unity and the Non-Aligned Movement, a world conference on sanctions against South Africa in June 1986.

British Ambassador Sir John Thompson, speaking against the conference that would cost the United Nations an estimated $900,000, asked, ''What could be said and done there that has not been said and done many times here?''

That resolution was approved 137-6 with 10 abstentions.

Other resolutions that were passed:

- Condemn South Africa for ''killings, arbitrary mass arrests and detention'' of people opposed to apartheid and call for the release of political prisoners and lifting of the state of emergency - 149-2 with 4 abstentions.

- Call for the United Nations to inform world public opinion of ''atrocities and crimes committed by the apartheid regime'' and ''to promote public action in support of the just struggle of the oppressed people'' - 150-0 with 5 abstentions.

- Condemn ''the continuing and increasing collaboration of Israel with the racist regime of South Africa'' - 102-20, with 30 abstentions.

- Proclaim the assembly's ''full support of the national liberation movements of South Africa'' and state that the ''freedom fighters of South Africa should be treated as prisoners of war'' - 128-8, with one abstention.

- Allocate $500,000 from the U.N. budget for use by the U.N. Special Committee Against Apartheid - 141-2, with 12 abstentions.

- Create and ask members to sign a Convention Against Apartheid in Sports to boycott all contacts with South African teams or athletes - 125-0, with 24 abstentions.

- Call for contributions to the U.N. Trust Fund for South Africa to help ''those persecuted under repressive and discriminatory legislation in South Africa'' - approved by consensus.