He was born in Ruse, Bulgaria. He was taught the rules of chess when he was eight years old by his father. In 1989 he won the World Under-14 Championship in Aguadilja, Puerto Rico, and in 1990 won the silver medal at the World Under-16 Championship in Singapore. He became a Grandmaster in 1992.
Topalov has been leader of the Bulgarian national team since 1994. At the Chess Olympiad in 1994 in Moscow he beat Gary Kasparov, and led the Bulgarians to a fourth-place finish. He has won a number of tournaments, and at the FIDE World Championship in New Delhi in 2000 reached the quarter-finals.