Abstract: This study was aimed to view the ways, bacterial DNA affect innate immunity, used macrophages to defeat bacterial DNA, then, evaluated the process of maturation, morphogenesis and killing activities. Cells obtained from peritoneal cavity lavage of 6-8 week old, pure Balb/c mouse, were harvested in complete tissue culture medium including RPMI, FBS 10%, penicillin, streptomycin. Cells were divided into 4 groups based on the type of received stimulator (DNAase, Bacterial DNA, FMLP 450 and Control). After 3 and 6 h from beginning of incubation period, macrophages adhered to bottom of the flasks, were studied for the number of adherent cells, morphogenesis maturation and induction of NBT, after removal of non-adherent cells. Regarding the number of adhered cells, bacterial DNA, as a rapid acting stimulator, showed the highest number of adhered cells and the most ideal morphogenesis, in 3rd h of incubation. In the 6th h of incubation, FMLP showed the most adherency and the best morphogenesis..Considering NBT reduction strength in the 3rd h, the highest percentage belonged to FMLP (42%), however, in the 6th h bacterial DNA allocated the highest rate with 95%. Can be DNA introduce as a strong stimulator with great performance over macrophage system. Besides other effects on the immunity system, it has drawn researchers attention for years and has resulted in taking beneficial steps in understanding innate immunity mechanisms. This genetic substance can be used as a lab stimulator in researches related to phagocytic system.