A Time-to-Digital Converter (TDC) is provided. The TDC includes a first TDC unit for receiving a first input signal and a second input signal, delaying the first input signal on a specific time basis using each of first delay blocks, generating first phase-divided signals by performing first phase division on signals of input/output nodes for each of the first delay blocks on a predefined Phase-Interpolation (PI) delay time basis, and outputting the second input signal and a phase-divided signal closest to the second input signal, among the first phase-divided signals, a time amplifier for independently time-amplifying the second input signal and the phase-divided signal closest to the second input signal, and a second TDC unit for delaying a phase-divided signal closest to the time-amplified second input signal on a specific time basis using each of second delay blocks, and generating second phase-divided signals by performing second phase division on signals of input/output nodes for each of the second delay blocks on a predefined PI delay time basis.