Tensile tests of notched thin film of pure titanium were carried out on the stage of a digital microscope. Tensile load was generated by the thermal expansion of a pair of polycarbonate loading plates which sandwiched the specimen. Since the thermal expansion coefficient of polycarbonate is much larger than that of pure titanium, the specimen was elongated with an increase in the temperature and successfully fractured at the end of the tensile test. The plastic deformation of the notched part of the specimen was observed during the test and the stress and strain were evaluated. The obtained stress-strain curves were compared with those obtained by a tensile testing device with a piezoelectric stage at the room temperature and 363 K which approximately corresponds to the maximum temperature of the thermal stress-actuated tensile test.