The present invention provides a microneedle array which is capable of effectively supplying retinoic acid to the skin and is effective for treating acne, pigmentation or wrinkles. This retinoic acid microneedle array comprises: a microneedle array which includes a microneedle substrate (5) and a microneedle (1) that is disposed on the microneedle substrate (5)； and a medicine which is retained by the microneedle (1) and comprises a water-swellable polymer and retinoic acid.
