Moral criticism is a prevalent phenomenon in today’s society. People are criticised, both online and in real life, for prejudiced attitudes, lack of eco-friendliness, or excessive meat consumption. Although moral criticism is intended to correct immoral behaviour, it can demotivate behaviour change and provoke interpersonal conflict between the critic and those criticised, when faced with defensiveness. However, there remain research gaps about contextual and dispositional causes of, and the role of moral emotions in, the psychological defensiveness to moral criticism. This thesis introduces four studies to address these gaps. Study 1 (N = 340) investigated the effects of moral licensing and criticism severity on defensive responses to sexist accusation. The results showed the moral licensing manipulation was not replicated and rendered no significant effect. However, severe criticism elicited more defensiveness than mild criticism. Study 2 (N = 506) aimed to manipulate contextual moral disengagement by reminding participants in the experimental condition of the responsibility of governments and corporations for climate change. However, the results showed such reminder unexpectedly increased pro-environmental intentions, and did not increase defensiveness to criticism of lack of pro-environmental intentions. Study 3 (N = 307) examined the effect of criticism’s content dimension (morality versus competence) on defensive responses to criticism of meat consumption. The results showed morality criticism triggered more defensiveness than competence criticism, as hypothesised. Study 4 (N = 316) tested the effect of publicness also on responses to meat consumption criticism. The results surprisingly showed that private criticism led to more defensiveness than public criticism, suggesting the negative impact of personalism embedded in private criticism. All four studies explored the roles of moral emotions and self-protective traits in responding to criticism. The results showed that anger was a defensive emotion whereas guilt was a non-defensive emotion. Nonetheless, anger, guilt, and shame were positively correlated with each other, suggesting a complex emotional state upon receiving criticism. Regarding personality traits, the studies showed narcissistic rivalry and victim sensitivity predicted defensiveness across contexts. Hostile sexism predicted defensiveness to sexist accusation. Dispositional moral disengagement predicted defensiveness only when the items were adapted to the context of the criticism. Together the four studies expand our understanding of contextual and individual differences which are associated with defensiveness to moral criticism. Theoretical implications, including the integration of different lines of criticism research, and practical implications, including strategies to mitigate defensiveness, are also discussed.