The sources of geothermal energy of Kamchatka are hydrothermal systems, local blocks of high heated rocks, and peripheral magma chambers of active volcanoes in particular. According to gravimetric, magnetic and seismic data, under the Avachinsky volcano there exists an anomalous zone which is suspected to be a peripheral magma chamber. It is localized at the boundary of the Upper Cretaceous basement and an overlying volcanogenous stratum at a depth of 1.5 km from sea level. Its geophysical data are as follows: the radius is 5.2±0.9 km; the density of rocks is 2.85 to 3.15 g/cm3, the velocity of longitudinal waves is 2200 m/sec, the viscosity of rocks is 105 to 108 poise. The temperature distribution in the near-chamber zone was calculated by clcctrointegrator at 0°C at the Earth's surface and 1000°C at the chamber surface for stationary and non-stationary (the period of 20 000 years) heating. Heat extraction may be possible if a system of artificial jointing iscreated. The capacity of a thermal reservoir with a volume of one cubic km at a depth of 5 km and a distance of 6 km from the volcano would be 2 x Ю14 kcal, extractable under non-stationary conditions, which could provide the work of power stations with a total capacity of 250 MW for a period of 100 years.