To provide a fluctuation amplification device for oscillator which improves quality of a generated random number without making worse the throughput per mounting area of an intrinsic random number generator.

A fluctuation amplification device 100 according to the present invention which amplifies fluctuations as temporal variation between two input signals includes: a variable buffer 101 which receives two input signals, delays the two respective input signal by a first delay time determined with a control signal as an external signal different from the two input signals, and outputs the signals; and a delay control part 102 which controls the first delay time by outputting the control signal to the variable buffer 101.