Mud volcano Gaynarja is located in 8-10 km southwest of the district center Shabran, located on the Pontian deposits of the Miocene, presented as a hill with a relative height of 60 m. and base diameter is 1.5-2 m. Radiometric measurements were carried out with SRP-88M and InSpector-1000 radiometers, which measure the exposure dose rate of gamma radiation in the range of 0-3000 μR/h and 0-10000 μR/h, respectively. The exposure dose rate of rocks and breccias on the territory of the Gainarca mud volcano varies widely - from 9.5 μR/h to 23 μR/h. The activity of rocks of the hilly breccia of the Gainarca mud volcano varies widely - from 106.4 to 515.12 Bq/kg. It reflects the overall level of integral gamma radiation and depends on the composition and content of radionuclides present in the rocks. In addition, two breccia samples were analyzed for the content of radionuclides Ra-226, Ra-228 and Rn-222. It was found that the content of Ra-226 is normal (90 and 92 Bq/kg at a rate of 370 Bq/kg), and radionuclides Ra-228 and Rn-222 were not detected.