Thermistor element, temperature sensor, and method for manufacturing the thermistor element

A method of manufacturing a thermistor element including a thermistor main body made of an electrically conductive sintered oxide and having a rectangular parallelepiped shape, and a first covering layer which has reduction resistance, said first covering layer covering an entire periphery of the thermistor main body and having an outer surface, at least a portion of which is an exposed outer surface exposed to the outside, wherein when a shortest distance in a straight line in the first covering layer extending from a starting point on the thermistor main body to the exposed outer surface is defined as an exposed layer thickness at the starting point, the first covering layer is formed such that the exposed layer thickness measured by using any vertex of the rectangular parallelepiped thermistor main body as a starting point is equal to or greater than the smallest one of exposed layer thicknesses measured by using, as starting points, points which are other than the vertex and located on three sides and three flat surfaces which form the vertex, the method comprising the steps of:

• press forming a green first covering layer, which is to become the first covering layer through firing, into a shape for encapsulating the thermistor main body;
• and
• firing the green first covering layer to thereby form the first covering layer.