To drive an inkjet printhead having an array of printing elements, where the first and second printing elements which discharge relatively different amounts of ink are arranged on the same array in a predetermined direction, print data for the first or second printing element is serially inputted, the inputted print data is sequentially stored, the stored print data is latched, a selection signal indicative of which of the first or second printing element is to be driven is inputted, a driving signal indicative of a driving period is inputted, and respective printing elements are driven in accordance with the latched print data, the selection signal, and the driving signal. Accordingly, it is possible to reduce the cost of the printhead having plural types of printing elements, which discharge relatively different amounts of ink, and possible to easily control driving of the printhead.