Urban environments differ in many aspects from natural or rural ones and thus pose challenges for many animal species. Some of these challenges have been connected to the observation that urban individuals of many animal taxa are bolder and more aggressive than their rural conspecifics. Apart from average behavioural differences between rural and urban populations, the variation of such behaviours within these populations may differ, enabling them to deal with the spatially and temporally heterogeneous habitats within cities. Here we tested average differences in behaviour as well as the components of variation in these behaviours in rural and urban populations of shrews. We chose two shrew species which differ in life history and time since synurbanization: the fast-paced Sorex araneus and the slow-paced Crocidura russula. We conducted repeated tests of boldness and aggression on 86 shrews. As predicted, urban shrews of both species were bolder than rural ones, although not more aggressive. Additionally, urban populations showed higher among-individual variation in both boldness and aggression, that is, urban individuals differed more from each other in their behaviour than rural individuals, independent of any within-individual variation. All differences were smaller in S. araneus than C. russula, possibly due to their generally bolder behaviour and shorter time since synurbanization. Large behavioural differences among the individuals of urban populations might allow them to better cope with the various and constantly changing challenges of city life for animals.