Although among feral cats, Felis catus, females copulate with multiple males, they do not accept all mounting or copulation attempts by males during their oestrous period. We observed eight female cats over their oestrous periods to examine whether or not female cats control paternity of their offspring in the field. The females were courted by between nine and 19 males, but copulated with only three to nine of them. Firstly, we compared female receptivity to male attempts among the eight females and tested how female traits affect their receptivity. Female receptivity to male attempts varied among the females both at mounting and at copulation. Females were more choosy at the time of copulation than at mounting. Females with a shorter oestrous duration and a lighter body weight tended to accept mounts more frequently than the females with a longer oestrous duration and a higher body weight. Older and lighter females tended to accept copulation more frequently than younger and heavier females. Females courted by fewer males per day also tended to accept copulations more frequently. Secondly, combining behavioural observations and determined kinship, we assessed whether females avoided copulating with their kin. The results showed that female cats avoid inbreeding with their close kin during copulation but not with distant relatives. Copulation attempts by kin males were less frequently accepted than those by nonkin males. Thirdly, we tested whether male age and body weight affect their mating success, but we failed to find any such correlation. These results support the hypothesis that female cats control paternity of their offspring during copulation.