The present invention relates to a resistance-based on-chip temperature sensor which may autonomously operate in a chip. A resistance-based on-chip temperature sensor according to an exemplary embodiment of the present invention includes: a first RC oscillator having an in-chip first resistor as a component; a second RC oscillator having an in-chip second resistor as the component; and a control unit determining the temperature of the chip according to what difference between the numbers of clocks output from the first and second RC oscillators, respectively is for the same time.