The present invention relates to a signal processing device and method, an imaging element and an imaging device. The signal processing device includes: an A / D conversion section for performing A / D conversion of the first signal, A / D conversion of the second signal, A / D conversion of the third signal, and A / D conversion of the fourth signal conversion; and a correlated double sampling processing section for generating a first output signal by performing correlated double sampling using the first and second digital data items, generating a second output signal by performing correlated double sampling using the third and fourth digital data items output signal, and generate a third output signal by performing correlated double sampling using the first and second output signals, the first digital data item obtained by A / D conversion of the first signal, the second digital data The item is obtained through the A / D conversion of the second signal, the third digital data item is obtained through the A / D conversion of the third signal, and the fourth digital data item is obtained through the A / D conversion of the fourth signal. D conversion obtained. The present invention can suppress deterioration of image quality.