In steady-state conditions, the number and distribution of lymphocyte populations are under homeostatic control. New lymphocytes are continuously produced in primary and secondary lymphoid organs and then achieve immune-competence within different tissues, and they must challenge with resident cells for survival. The first step in the study of tissue lymphoid cells is their isolation in intact and viable form appropriate for establishment of in vitro culture systems. For reasons of simplicity, cell purity, cell yields and various purposes, lymphocytes obtained from different tissues in different labs were subjected to diverse protocols. To fully elucidate the nature of the local immune system as well as to adequately study the innate role of lymphocytes in liver, intestine, lung and uterus, we briefly reviewed the characterization of resident lymphocytes, and additional information on those cells from non-lymphoid tissues by using the recommended operation procedure was also presented.