The present study aimed at investigating whether the effects of intergroup contact on support for discriminatory behaviours against immigrants was mediated by perceived threat from immigrants and positive beliefs toward immigrants. Using data from the Italian national survey on "Discrimination by Gender, Sexual Orientation and Ethnic Origin," which followed a multi-stage stratified cluster sampling procedure, a representative sample of 5509 Italian residents (53.4% women), aged 18 to 74 years, participated. Findings showed that contact with immigrants was negatively related to perceived threat, and positively related to positive beliefs toward immigrants. Mediational analysis conducted by structural equation modelling, indicated that support for discriminatory behaviours was positively associated with perceived threat, and negatively associated with positive beliefs toward immigrants. Both variables together mediated the relationship between contact with immigrants and support for discriminatory behaviours against immigrants; individually, indirect relationships were also significant. To promote interaction between natives and immigrants by reducing the perceived threat and strengthening positive beliefs toward immigrants might lessen support for discriminatory behaviours against immigrants. © 2019 International Union of Psychological Science.