•Snow leopards chose wild ungulates even in landscapes dominated by livestock.•Snow leopards appeared to kill livestock opportunistically.•Adult males killed more livestock and were more vulnerable to retaliatory killing.•Avoiding rugged pastures and minimizing stragglers will reduce livestock losses.•Snow leopards removed much more prey than previous estimates of kill rates suggest. Livestock predation is an important cause of endangerment of the snow leopard (Panthera uncia) across its range. Yet, detailed information on individual and spatio-temporal variation in predation patterns of snow leopards and their kill rates of livestock and wild ungulates are lacking. We collared 19 snow leopards in the Tost Mountains, Mongolia, and searched clusters of GPS positions to identify prey remains and estimate kill rate and prey choice. Snow leopards killed, on average, one ungulate every 8days, which included more wild prey (73%) than livestock (27%), despite livestock abundance being at least one order of magnitude higher. Predation on herded livestock occurred mainly on stragglers and in rugged areas where animals are out of sight of herders. The two wild ungulates, ibex (Capra ibex) and argali (Ovis ammon), were killed in proportion to their relative abundance. Predation patterns changed with spatial (wild ungulates) and seasonal (livestock) changes in prey abundance. Adult male snow leopards killed larger prey and 2–6 times more livestock compared to females and young males. Kill rates were considerably higher than previous scat-based estimates, and kill rates of females were higher than kill rates of males. We suggest that (i) snow leopards prey largely on wild ungulates and kill livestock opportunistically, (ii) retaliatory killing by livestock herders is likely to cause greater mortality of adult male snow leopards compared to females and young males, and (iii) total off-take of prey by a snow leopard population is likely to be much higher than previous estimates suggest.