We studied the effect of several environmental and reproductive variables on the reproductive performance of captive European wildcat (Felis silvestris silvestris, Schreber 1777) females in Spain. We collected reproductive data from 34 females that produced 77 litters and 295 kittens. The youngest females that gave birth were 12 months old, whereas the oldest was11+ years old. On average, females giving birth were 3.8 years old (n=62), with a mode of one+ years old. Mean litter size was 3.7 kittens±1.0 (range: one to six; n=77 litters), with three or four kittens comprising 67.5% of litters. Mean litter size declined significantly from spring to late summer. Females kept in big enclosures and during a Feline Immunodeficiency Virus (FHV-I) outbreak showed higher mean litter sizes. Births occurred from March to August, most occurring during the spring (91% of litters; n =65). Late litters were mostly from second gestations (following the loss of the first litter of that year) and females in their first gestation. Females giving birth in March were significantly older than those giving birth later, especially from May to June-August. Experienced females gave birth in March and April. The sex ratio was 1:1, with most of the litters containing both sexes. Outside a disease epidemic episode, the main causes of known mortality were infanticide (54%) and diseases (44%). Kittens affected by infanticide had lower survival than those affected by FHV-I. Our results show that the wildcat has low reproductive plasticity. This may partially explain its fragmented distribution across Europe. Although our work was in captivity, it presents new knowledge on the reproductive biology of the wildcat, which is important both for conservation of wild populations and for the management of captive ones, for example, the role of seasonality and environmental variables on litter size, or the causes of kitten mortality