Currently the problem of theoretical calculation and experimental determination of the isotopic exchange rate in mixes of hydrogen isotopes is open. There are a few experimental data on exchange rate constants that are rather discrepant. Of interest are experimental data on isotopic exchange rate in a gaseous mix of hydrogen isotopes at high pressures (thousands atmospheres). Raman spectroscopy is a relevant method for obtaining objective data on isotopic exchange rate in a gaseous mix of hydrogen isotopes, since it allows one to determine a gaseous mix composition without sampling in a real time. The paper describes equipment which allows registration of Raman spectra for gases under pressure up to 400 MPa and experimental data determining the constants of isotopic exchange rate in a protium-deuterium mix at pressures up to 200 MPa.