A pulsed electromagnetic-wave generator includes an excitation light source, a laser resonator, a pulse generating unit, and a wavelength converting unit. Excitation light from the excitation light source enters the laser resonator. The pulse generating unit is configured to generate a pulsed light group including at least two or more pulses with different frequencies (ω) and different oscillation timings (t) in one excitation process of the excitation light source, an oscillation frequency difference (Δω) between the pulses in the pulsed light group being an integral multiple of a Free Spectral Range (FSR) of the laser resonator. The pulsed light group enters the wavelength converting unit. The wavelength converting unit is configured to generate a pulsed electromagnetic wave in which a wavelength of each pulse in the pulsed light group is converted.