Volodymyr Radchenko, a former head of the National Security Service, was approved by 251 of the parliament's 450 members, or 25 more than the required 226 minimum.
Radchenko, 58, said that in his new post he would coordinate the work of law-enforcement agencies. Before his appointment, he served as the defense minister and the interior minister. From November of last year until the present, he worked as an aide to Prime Minister Yanukovych.
Radchenko's appointment is another blow to President Viktor Yushchenko, who has seen several of his key Cabinet allies sacked by parliament's governing coalition since he agreed in August to appoint arch rival Yanukovych to the post of prime minister in an effort to resolve a months-long political crisis.
The legislature, in which Yanukovych leads a 246-strong majority coalition, voted in December to dismiss Foreign Minister Borys Tarasyuk and Interior Minister Yuriy Lutsenko, both presidential appointees.
Yushchenko, swept into power on the back of the 2004 "orange" revolution, is determined to take Ukraine into NATO and the European Union, but his efforts to forge closer ties with the West have been staunchly opposed by the pro-Russian Yanukovych.