In a thin film magnetic head of the present invention, lead formation patterns of a first lead for connection between a lower shield layer and a first extraction electrode portion and a second lead for connection between an upper shield layer and a second extraction electrode portion are each formed so as not to have an overlapping portion with a heatsink layer but to bypass the heatsink layer when observing from the upper shield layer side toward the lower shield layer in a transparent state in plan view. Therefore, it is possible to increase an effect of heat radiation to the substrate side on the basis of the presence of the heatsink layer to thereby limit propagation of heat to a magnetoresistive effect layer as much as possible and further to achieve a drastic improvement in recording and reproducing characteristics at high recording frequencies, i.e. frequency characteristics (f characteristics) in a high frequency region.