Recent studies suggest that individual variation in behaviour of prey individuals may cause distinctive responses to nest predators and cooperation with conspecifics. We assessed individual differences during a novel object test and whether these responses were related to nest failure and survival of females during incubation. We additionally carried out experimental trials in natural field conditions using a stuffed pine marten, a principal nest predator, to test for a relationship between neophobia and mobbing predators. Our results show that antipredator responses of breeding great tits are dependent on their personality and personality type of neighbouring conspecifics. We found that neophilic individuals (those that rapidly resumed feeding of nestlings in the presence of a novel object) have an advantage over neophobic individuals (those that slowly resumed feeding of nestlings in the presence of a novel object) in their reproductive success, as measured in numbers of successful nests and of females that survived. Furthermore, neophilic-neophilic pairs exhibited stronger antipredator mobbing responses than neophobic-neophobic pairs. Results show that consistent individual differences in response against novel objects and antipredator behaviour are related, and that these responses are important predictors of nest failure in breeding great tits.