PURPOSE: To make a high density thermal recording head free from disconnection even when an underglass is laminated only on a part of a substrate by forming two layers of conductive layers in an area the thickest in a staircase- shaped underglass layer.

CONSTITUTION: A staircase-shaped underglass layer 5 is formed on a necessary part of an electrical insulation substrate 1 with a better heat conductivity and a first conductive layer 6 is provided in the thickest area W1. Then, when a second conductor layer 5 is provided covering the substrate 1 together with the layer 5, the layers 6 and 5 are laminated on the area W1 becoming thinner in the layer 5 to prevent the generation of a pinhole or the like. This enables the making of a high density thermal recording head free from the possibility of disconnection simply and accurately even when the underglass is laminated only on a part of the substrate.