Ihor Murashov was detained on his way from Europe's largest nuclear plant to the town of Enerhodar around 4 p.m. (1300 GMT) on Friday, company chief Petro Kotin said in a statement.
"He was taken out of the car, and with his eyes blindfolded he was driven in an unknown direction," Kotin wrote on the Telegram messaging app, adding there was no immediate word on Murashov's fate.
The Zaporizhzhia plant has been a focal point of Russia's seven-month invasion of Ukraine, as Moscow and Kyiv accuse each other of shelling the facility, risking a nuclear disaster.
Ukrainian President Volodymyr Zelenskiy has called for area around the plant, which is staffed by Ukrainians, to be demilitarized.
Murashov "bears main and exclusive responsibility for the nuclear and radiation safety" of the plant and his detention "jeopardizes the safety of operation of Ukraine and Europe's largest nuclear power plant", Kotin said.
He called on Russian forces to "stop immediately the acts of nuclear terrorism towards the management and personnel" of the plant and release Murashov.
(Reporting by Pavel Polityuk in Kyiv; Writing by William Mallard; Editing by Kim Coghill)