BEIJING (AP) _ A Soviet delegation led by Deputy Foreign Minister Igor Rogachev arrived Friday for a second round of talks on resolving disputes about the 4,650-mile Chinese-Soviet border.

The first round was held in Moscow in February, with the two sides agreeing to begin an examination of the full length of the border starting from the eastern side.

''We came here to work and work very hard,'' Rogachev said upon arrival at the airport, where he was greeted by his Chinese counterpart, Vice Foreign Minister Qian Qichen.

Rogachev said he did not anticipate any breakthroughs in the discussions, expected to last about two weeks.

''It's very hard to expect any concrete results after one or two rounds of talks,'' he said.

China and the Soviet Union have long been at odds over the boundary line along waterways and over the islands of the Amur and Ussuri rivers dividing Soviet Siberia and northeastern China. There were armed clashes along those rivers in 1969, bringing the two countries to the brink of war.

Negotiations to solve the border disputes were suspended in 1979 after the Soviet military incursion into Afghanistan. They resumed this year amid slowly warming relations between the two nations.

Soviet leader Mikhail Gorbachev, who has actively sought an easing of tensions between Moscow and Beijing, last year conceded Chinese sovereignty over several islands in the middle of the two rivers. Previously the Soviets had insisted that the border ran along the Chinese bank of the rivers.

China's Foreign Ministry spokesman Ma Yuzhen on Wednesday said ''all the questions'' concerning the boundary will be taken up.

Rogachev also said that in the first round the Chinese had not attempted to link the border issue with Chinese demands that Moscow end its support for Vietnam in its 1979 invasion of Cambodia, where a pro-Hanoi government was installed.

China insists that it will not normalize political relations with the Soviet Union until the Kremlin removes the ''three obstacles'' of Cambodia, the Soviet military occupation of Afghanistan and the concentration of Soviet troops along the Chinese-Soviet border.