Resident memory CD8 T cells (T RM) are a nonrecirculating subset positioned in nonlymphoid tissues to provide early responses to reinfection. Although T RM are associated with nonlymphoid tissues, we asked whether they populated secondary lymphoid organs (SLO). We show that a subset of virus-specific memory CD8 T cells in SLO exhibit phenotypic signatures associated with T RM, including CD69 expression. Parabiosis revealed that SLO CD69+ memory CD8 T cells do not circulate, defining them as T RM. SLO T RM were overrepresented in IL-15–deficient mice, suggesting independent regulation compared with central memory CD8 T cells and effector memory CD8 T cells. These cells were positioned at SLO entry points for peripheral Ags: the splenic marginal zone, red pulp, and lymph node sinuses. Consistent with a potential role in guarding SLO pathogen entry points, SLO T RM did not vacate their position in response to peripheral alarm signals. These data extend the range of tissue resident memory to SLO.