The purpose of the present study was to examine whether (repeated) exposure to cyberbullying as a bystander has an impact on early adolescents' moral evaluations in terms of a decrease in empathy and a shift towards a more tolerant attitude towards cyberbullying. A two-wave panel study with a 6-month time interval was conducted among a sample of 1412 adolescents aged 10-13. Cross-lagged panel analysis was used to investigate relationships over time between being a bystander of cyberbullying, empathic responsiveness towards distressed others, and the attitude towards cyberbullying, while taking into account involvement in cyberbullying as a victim or a perpetrator. The results indicate a negative relationship between standing by at Time 1 and empathic responsiveness at Time 2. In other words, exposure to cyberbullying as a bystander at Time 1 predicted subsequent lower levels of empathic responsiveness at Time 2. The attitude towards cyberbullying at Time 2 was not influenced by seeing more cyberbullying acts at Time 1. Further implications of the results for prevention and intervention, and for future research are discussed. (C) 2016 Elsevier Ltd. All rights reserved.