A delay line-based time to digital converter includes: a coarse counter for counting a pulse of a timing clock and measuring a time when an edge of an input signal is detected; a fine time interpolator including a plurality of first delay elements and a plurality of second delay elements, a delay line with the input signal as an input, and a flip-flop unit with outputs of the first delay element or outputs of the second delay elements as inputs and the timing clock as an operation frequency; and a timestamp generator for receiving a digital value on a time measured by the coarse counter and the fine time interpolator, and generating a timestamp on the input signal by using the received digital value.