Previous research has shown that Typhonium flagelliforme (Lodd.) Blume and Phyllanthus niruri L. in single form act as an immunomodulatory agent. The aim of this study was to establish how the combined ethanolic extracts of T. flagelliforme and P. niruri affect the immune system. The immunomodulatory activity of this combination was tested by treating Sprague–Dawley rats for 17 days. A total of 30 rats were divided into six groups (control, T. flagelliforme ethanolic extract, P. niruri ethanolic extract, and three various doses of combined ethanolic extracts of T. flagelliforme and P. niruri). On day 18, the rats were killed and blood was taken for immunological assessment (macrophage phagocytic activity, lymphocyte proliferation, and antibody titer). The combined extract of T. flagelliforme and P. niruri did not affect the phagocytosis of macrophages and IgG production; however, they were able to increase the proliferation of lymphocytes.