Knowledge about a species’ reproductive parameters such as breeding behaviours is a vital building block for essential conservation actions, especially for endangered species. Despite this, there is a considerable knowledge gap about the snow leopard (Panthera uncia) maternal behaviours, as well as the timing of den independence for the cubs. It has been assumed that female snow leopards change their behaviours post-denning and that the cubs leave their den together with their mothers around two to three months of age. However, until this day no quantitative data has been used to analyse female behaviours post-denning and when the cubs leave their den. I analysed pre- and post-denning activity for seven GPS-collared snow leopard females in Tost Mountains of southern Mongolia during the years 2010 to 2019. With linear mixed models and generalized linear mixed models, I found that female snow leopards with small cubs changed their behavioural patterns and space use by decreasing their monthly home range size, compared to females with older or no cubs. When the cubs became six months old, there were no detectable differences in these behaviours which suggests that the cubs started to travel continuously with their mother at the age of 5-6 months. The rate at which the collars successfully acquired positions decreased considerably during the early phase of denning when the female spent considerable time at the den sites where the collars could not communicate with the satellites. The age of the cubs when the female left the den ranged from 21-61 days (mean =44 days), suggesting that snow leopard females use their dens for 1.5 ± 0.5 months. This study provides the first estimate of the extent of den use by snow leopards, as well as the first estimates of post-denning behavioural patterns for snow leopard females and their cubs.