The man, who worked as the director of SBU in Kiev and the Kiev Region area, was arrested on suspicion of working for Russian security services, the source said.
Currently, the SBU is checking all of their employees for possible ties with foreign security services.
Earlier this week, the Ukrainian parliament sacked Valentin Navilaychenko from the position of the head of the country's security service on President Petro Poroshenko's suggestion.
Nalivaychenko was questioned by the country's prosecutors after he accused Deputy Attorney General Anatoly Danylenko of covering up an oil depot fire near Kiev. The Ukrainian media branded the situation a confrontation between the country's general prosecutor's office and the security services.
