Russia’s membership in the United Nations after the dissolution of the Soviet Union in 1991 was the succession of the Soviet Union’s seat, including its permanent membership on the UN Security Council. The succession was supported by the USSR’s former members and was not objected to by the UN membership; Russia accounted for about half the Soviet Union’s economy and most of its land mass; in addition, the history of the Soviet Union began in Russia. If there was to be a successor to the Soviet seat on the Security Council among the former Soviet republics, these factors made Russia seem like a logical choice.

More information here:

http://en.wikipedia.org/wiki/Russia’s_membership_in_the_United_Nations

If this or another answer here proves helpful in your research, you can encourage good answers by choosing one answer as the “best answer.”

Cheers,

Bruce

Any country who’s anybody joins the UN. It is just good sense.