Abstract: The research subject is the peat permafrost mounds on the northeast of Bolshezemelskaya tundra. The authors study the permafrost mounds at different stages of development – from the adolescent and growing to the mature and broken. The mature permafrost mounds are from 3 to 4,7 m high; some of them have the signs of primary breaking in the form of stains of bare peat or cavities on the surface. The height of adolescent permafrost mounds usually doesn’t exceed 1,5 – 2 m; the broken mounds look like peat mounds, surrounding the lows. The width of peat, superposing the mounds, varies from 0,8 to 1,2 m on mature mounds to 0,3-0,6 m on broken mounds. The authors sample the peat on mounds and lows (at 5-10 cm intervals); establish the radiocarbon age, the composition of carbon and nitrogen and the isotope composition of peat carbon. Radiocarbon dating shows that the studied mounds had formed in the period of Holocene optimum; the highest mounds formed about 7,7 – 4,8 thousand years ago. The authors show that within the limits of the studied mound landscapes in Holocene, the conditions of water intrusion, the composition of vegetative cover and the temperature of vegetation periods continually changed. Peat accumulated in the conditions of high water intrusion; the permafrost condition of peat had determined its low decaying and humification. Both in the period of Holocene optimum and at the present time, permafrost mounds develop cyclically, that is determined by both climate changes (air temperature and the snowiness of winters) and local factors, including the change of masses humidity.