Coffee is one of the most familiar beverages to modern human adults, but its bio-physiological effect has not been clearly elucidated. It was known that more than one thousand chemicals were included in the ordinary coffee extract. Among them, the caffein and chlorogenic acid (caffeoylquinic acids) are most abundant and have been investigated by many authors so far. In order to know the real cellular effect of whole coffee extract elements, the dialyzed coffee extract (DCE)1) was made to get coffee elements less than 1000 Da molecular weight, which are freely absorable through gastrointestinal tract. It was directly treated in the culture of RAW 264.7 cells, a murine macrophage lineage. RAW 264.7 cells were treated with DCE equivalent to 2.5 cups of coffee (DCE-2.5), DCE-5, and DCE-10 for 12 hours, and their protein extracts were examined by histological observation and immunoprecipitation high performance liquid chromatography (IP-HPLC). RAW 264.7 cells differently expressed the proliferation-related proteins depending on the dose of DCE. DCE-2.5 and DCE-5 enhanced the cellular growth of RAW 264.7 cells by increasing the expression of β-actin, PCNA, Ki-67, MPM2, MAX, cMyc, E2F-1, and Rb-1, and by decreasing the expression of MAD and p21. These proliferation-related proteins were rarely affected by DCE-10. DCE-2.5 and DCE-5 induced the cellular proliferation of RAW 264.7 cells by the signaling of E2F-1 and cMyc, respectively, but these cellular effects almost disappeared in DCE-10. Therefore, it was presumed that the low dose of coffee, DCE-2.5 and DCE-5 might be effective for the proliferation of murine macrophages, RAW264.7 cells, contrast to the high dose of coffee, DCE-10. It was also suggested that the low dose of DCE-2.5 and DCE-5 be helpful to increase the innate immunity in vivo by increasing the cell number of macrophages in contrast to the high dose of DCE-10.