Abstract: Drawing on the idea of the Social Identity Theory, the group engagement model (GEM) developed both the group value model and the relational model. GEM purported that procedural justice affects people’s mind and behavior through social identity perception. GEM generalized four components of procedural justice, differentiated pride and respect, and told us the different effects on behavioral engagement which brought by resource judgements and identity judgements. Generally, GEM is helpfull to explain the intra-group behavior, it also expands the vision of the Social Identity Theory. However, more researches are needed for further validation and consummation for various person and under different cultures.

Key words: GEM, social identity, respect, pride, procedural justice