A thin-film thermistor element which has an electrically insulating substrate having first and second surfaces opposite to each other and also having a pair of through-holes defined therein so as to extend completely across the thickness thereof, and a pair of electrode films each including a body portion of large surface area and a generally comb-shaped portion continued outwardly from the body portion. The electrode films are formed by the use of a firing process on the first surface of the substrate with the respective comb-shaped portions thereof confronting with each other. First and second electroconductive films are also formed on respective surrounding wall faces defining the corresponding through-holes in the substrate in electrically connected relationship with the body portions of the associated electrode films. A temperature sensitive resistance film is formed by the use of a high frequency sputtering process on the first surface of the substrate so as to overlay the electrode films. A method of making the thermistor element is also disclosed.