A pipeline type analog-digital converter includes a first to an N-th (N is an integer of not less than 2) stages (101 to 10N) brought into cascade connection and converting an analog signal input from a preceding stage to a digital signal of a predetermined bit and outputting the digital signal. Each of the first to the (N−1)-th stages (101 to 10N−1) includes an analog-digital converter circuit including comparators comparing an analog signal with reference potential being determined in advance and mutually different in parallel. The first to the (N−1)-th stages are in redundant configuration with the comparators of the stage including an auxiliary comparator.