With Mykola Chuzhykov, Anatoly Grishin and Volodymyr Morozov, Vyacheslav Ionov was the member of one of the top kayak fours in the middle of the 1960s. Together they won the Olympic gold in 1964, World 10K K4 title in 1966 and European Championships 10K K4 bronze in 1965. In 1967, Chuzhykov was replaced by Valery Didenko and the new team won the European 10K K4 title and 1,000 K4 silver in 1967. Domestically, Ionov won 10 Soviet titles, all in K4 – in 1962, 1964, 1966 and 1967 in the kilo and in 1961-63 and 1965-67 in the 10K. After finishing his sporting career, Ionov worked as a canoeing coach in his native Moscow.