Abstract: Culture conditions affecting protease production by Bacillus licheniformis isolated from Tihamet Aseer, Saudi Arabia were investigated. The bacterium strain gave a maximum protease production of 221 U mL-1 when growing in a casein broth medium after 36 h compared with gelatin broth medium. Optimum pH and temperature of protease production were 8 and 50°C, respectively. The highest level of protease production in the presence of soybean meal as a carbon source and the peptone as a nitrogen source was obtained. The protease was optimally active at pH 9 and 55°C . The enzyme was stable at temperature range of 60-65°C during the period tested (1h) and retaining more than 85% of its activity at 70°C. These properties make the enzyme suitable for detergent industry.