The immune system has an important role in human health. The innate immune-system defends the host against infection by phagocytes the antigen, which is the role of macrophage cell. Red Fruit (Pandanus conoideus Lam.) had been empirically proved to increase body immune system. The aim of this study is to know the effect of Red Fruit toward the macrophage’s phagocytotic activity. This research was acted invitro on Swiss Webster mice’s macrophage cell culture, which was exposured by Red Fruit extract (concentration 0,25ug/dl; 0,50ug/dl; 1,00ug/dl; 2,50ug/dl; 5,00 ug/dL) in 5’, 10’, 30’, and 60’. The percentage of activated macrophages was counted, compared between treatment group and negative control group (aquadest). The data was processed by One Way Anova and Tukey HSD statistical methods. The result shows that 10’, 30’ and 60’ exposured of Red Fruit extract could increase Macrophage’s activity significantly (p=0,000). The optimal dose of Red Fruit extract which could increase the activity of macrophage is 0,25 µg/dl. With 10’, 30’ and 60’ exposured of Red Fruit could increase the phagocytotic activity of macrophages 76.15% ug/dl, 65.32% ug/dl, and 83.41% ug/dl. It can be concluded that the exposurd of Red Fruit extract 10’, 30’ and 60’ could increase macrophage’s phagocytotic activity, with the optimal dose is 0,25 µg/dl.