The present invention aims to administer active ingredients efficiently and simply through the skin. For this purpose, a microneedle device 1 has a microneedle base 2 and microneedles 3 capable of piercing the skin and being 300 to 500 µm in height disposed on the base 2, wherein at least a part of the surface of the microneedles 3 and/or the microneedle base 2 is coated with a coating agent containing an active ingredient and a coating carrier, and a blending ratio of the active ingredient and the coating carrier is 10:0.1 to 1:10.
