TIM (T-cell immunoglobulin and mucin) gene, firstly found on mouse chromosome 11B1.1, is expressed by various kinds of immune cells, especially antigen presenting cells. TIM is involved in both innate immunity and adaptive immunity. Some TIM proteins can bind different ligands, exerting dual influence on T cells. The abnormal expression of TIM is associated with many kinds of diseases, making TIM a new target for pharmacotherapy. The relation of TIM and Tregs has cast new lights on transplantation immune-tolerance. This paper focuses on the immune regulation function of TIM family.