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An alkaline protease producer haloalkaliphilic bacteria (isolate Vel) was isolated from west coast of India. It was related to Bacillus pseudofirmus on the basis of 16S r RNA gene sequencing, lipid profile and other biochemical properties. The protease secreted by this bacteria was purified 10-fold with 82% yield by a single step method on Phenyl Sepharose 6 Fast Flow column. The apparent molecular mass based on the sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) was estimated to be 29000Da. The K_m and V_max towards caseinolytic activity were found to be 2mgml⁻¹ and 289.8μgmin⁻¹, respectively. The enzyme was active over the pH range of 8.5–12.0, the optimum being 10–11.0. The purified enzyme when kept at 45°C and 50°C for 40min retained 92% and 85% protease activity, respectively. Effect of NaCl concentration on protease activity showed that the enzyme was slightly …