The simplest way to get to the city center is to take a marshrutka. They leave very regularly, cost 30UAH, and terminate to the plaza behind the main train station, close to the Metro. A taxi will cost 250-500UAH, with the taxis operated the people who meet travellers off the plane with the promise of taxis the most expensive .
POLIT: operates a regular bus service between airport and Kiev city center (ploshcha Peremohy and Central Railway station (bus schedule). Buses depart frequently and the cost is 25UAH. Tickets are bought from the driver. On average, it takes 40-70 minutes to get to city center by bus.