[en] The measurements were performed on the neutron beam of the IBR-30 reactor. In distinction from the recent published works, thermal neutrons were separated by the flight time. The ³⁵Cl(n,p) reaction cross section was determined by a comparison with the (n,p) and (n,α) reaction cross sections on ¹⁴N and ⁶Li. The ionization chamber was used to register the charged particles. Previously, investigations of the reaction on ³⁵Cl were carried out mainly with the help of the activation method. Only in one experiment, reported over 50 years ago, an ionization chamber was used. Our measurements were performed with 8 targets of NaCl, KCl, LiF and C₅H₅N₅ with different thicknesses. The ³⁵Cl(n,p)³⁵S reaction cross section for thermal neutrons turned out to be equal to (575±13) mb, that is noticeably higher than most of the recent published values. (author). 19 refs., 5 figs., 4 tabs