Аннотация:Communication radio signals between an orbital spacecraft (SC) and a ground tracking station (GTS) experience a frequency shift proportional to the positional difference of their gravitational potentials. The effect constitutes an experimental basis of the general theory of relativity (GR) as one of the aspects of Einstein's equivalence principle (EEP). The article presents the results of precision measurement of the effect using frequency standards placed on the SC and GTS. Data from special “gravitational sessions” of radio communication accumulated during the “RadioAstron” (RA) space radio telescope mission in 2015 2019 were used. Scrupulous analysis of these data allows to confirm the correspondence between theory and experiment with high accuracy: the violation parameter (deviation from GR) was 1.57 ± 3.96 · 10−5.