A multilayer coil device is formed by alternately stacking a plurality of insulating layers and a plurality of substantially spiral coil patterns. In the multilayer coil device, the number of turns of each of the substantially spiral coil patterns is more than one. Each of the substantially spiral coil patterns has a protrusion protruding toward a center of the substantially spiral coil pattern. The protrusion is located in a specific region where the number of coil pattern portions that cross a virtual line extending radially outward from the center of the coil pattern is smaller than that in another region of the substantially spiral coil pattern. The protrusion is provided as an additional part of a coil pattern portion that is closest to the center of the substantially spiral coil pattern in the specific region.