A buried channel CCD is described wherein buried CCD elements are formed on a semiconductor substrate of P-type material and formed in a semiconductor area of N-type material. Transfer electrodes are provided to which a driving pulse is applied. The driving pulse is a three-level pulse having, at different time points, first, second and third levels, during at least one part of a time period in a charge transfer period and a charge integration period, the first or second level of the three-level pulse is applied to selected transfer electrodes so that part of signal charges in the buried channel are drained through the semiconductor area into the semiconductor substrate; and in the charge transfer period, the second and third levels are alternately applied to the transfer electrodes.