Brucella is pathogenic bacteria that cause animal and human brucellosis. Currently, the mechanism behind the pathogenesis of Brucella remains unclear. For this reason omp10 mutant was constructed to examine the impacts of the outer membrane protein 10 (Omp10) on bacterial survival, virulence, phagosome-lysosome fusion, and apoptosis induction, as assessed in appropriate in vitro (cell culture) and animal models. Results showed the omp10 mutant was dramatically attenuated for survival in macrophages and mice than the parent strain 2308. With decrease in the spleen/body weight ratios of mice infected with omp10 mutants were noted, inhibition of phagosome-Lysosome fusion was dramaticly impaired, and profound increase of apoptosis rate after exposure of RAW264.7 to omp10 mutants at 12 h, 24 h and 48 h compared to RAW264.7 exposed to 2308. Results indicate that Δomp10 mutant would affect its survival and pathogenicity.