Wavelength-tunable source of pulsed laser radiation for VIS-NIR spectroscopy which consists of a pump source (1) forming bursts of picosecond pulses of high pulse repetition rate, and a synchronously pumped optical parametric oscillator (2). The pump source (1) comprises a solid-state regenerative amplifier (31) having one or two electro-optical switches (32,33) inside its resonator (44). The switches create partial transmission of the resonator for a time interval longer than a resonator roundtrip time, and eject a part of energy of a pulse circulating inside. Bursts of 5-10 ns duration are formed, which are filled with high peak power picosecond pulses. Pulse repetition rate of the order of GHz of pump pulses allows the construction of a compact optical parametric oscillator. The whole set of parameters ensures high energy efficiency, stability and an ability to provide output pulse bursts repeating at up to 10 kHz repetition rate.