Kolev started his football career at
Lokomotiv Sofia, where he was established and played 10 years, becoming their captain winning a
league in 1978 and a
Bulgarian Cup in 1982. On 21 July 1982, the release of his compatriot
Hristo Bonev from
AEK Athens brought his transfer to the
Greek club for a fee of 3.5 million
drachmas. Kolev had a good recommendation by Bonev and the reputation of him being a complete midfielder raised the club's expectation that would help them to escape from their competitive decline. Kolev did not live up to expectations, making a total of 12 appearances with AEK in which only one was as a starter. He continued his career at
Shumen, that was also disappointing. The inaction at AEK and the will of the footballer himself, led him to the decision to retire as a footballer in 1985, at the age of 33. ==International career==