A digital temperature sensor includes a current generation circuit, an oscillation circuit, a conversion circuit and a calculation circuit. The current generation circuit generates a proportional to absolute temperature (PTAT) current and a complementary to absolute temperature (CTAT) current. The oscillation circuit generates a first clock signal having a first cyclic period based on the PTAT current and generates a second clock signal having a second cyclic period based on the CTAT current. The conversion circuit generates a first temperature code based on the first clock signal such that the first temperature code decreases as the operation temperature increases and generates a second temperature code based on the second clock signal such that the second temperature code increases as the operation temperature increases. The calculation circuit calculates a difference between the first temperature code and the second temperature code and generates a corrected temperature code based on the difference.