Childhood experiences of animals and current attitudes towards animals were assessed using a questionnaire, which was completed by 227 Japanese students and 174 British students. Pet ownership in childhood, as well as contact with other animals and negative experiences of pets, were used as the independent variables; current attitudes towards pets and other animals were the dependent variables. There were some differences between Japan and the UK: in childhood, the British students had had significantly more pets and more animal-related experiences, such as visiting animal shelters and livestock farms, than had the Japanese students. Their current attitudes were also more positive, and they showed a greater interest in animal welfare issues than did the Japanese students. In both countries there was a positive association between childhood pet-keeping and current favourable attitudes to pets, as measured by the Pet Attitude Scale. Open-ended responses also suggested that the roles of pets for children are perceived in similar ways in Japan and the UK. Adult attitudes to pets and interest in animal welfare seem to be greatly influenced in both countries by childhood experiences of animals, including pets, and may therefore be a general phenomenon.