Marine organisms are among the prominent and abundant sources of 1-O-alkyl-sn-glycerols, including chimyl alcohol (CA), batyl alcohol and selachyl alcohol. These biologically active compounds are precursors in plasmalogen and phospholipid biosynthesis, which are the main irreplaceable components of cell membranes. The results of this study demonstrate that CA promotes the activation of immune processes in the mouse spleen and in the mouse macrophage cell culture RAW 264.7. We studied the effect of CA on the spleen weight, as well as on the proliferation process and expression of interleukin-1β (IL-1β) and CD86 – a marker of the proinflammatory M1-type macrophage cell surface in experimental animals. We used the RAW 264.7 macrophage cell culture to assess the CA cytotoxicity, its effect on reactive oxygen species (ROS), nitric oxide (NO) production and lysosomal activity, as well as IL-1β and CD86 expression in vitro. In vivoand in vitro experiments have shown that CA: (1) enhances cell proliferation without changing the spleen’s weight, (2) increases the activity of the proinflammatory marker CD86, (3) increases the level of ROS/NO/lysosome activity, and (4) does not affect the level of IL-1β. Our study reveals that CA has a complex immunostimulation effect in vitro and in vivo, which opens up prospects for further study of its biological activity.