The snow sheep, Ovis nivicola, is endemic to the mountain ranges of northeastern Siberia. The remoteness and harsh climatic conditions of their habitat make these wild sheep the ideal candidates to study mammalian adaptation to extreme environments with regard to elevation and temperature. As a first step towards this goal, we generated a ~2.62 Mbp genome assembly of snow sheep using long reads of PromethION sequencing technology. The genome assembly consists of 7,157 scaffolds with N50 length of ~2.01 Mbp