Proteases correspond to the majority of worldwide enzyme sales and find a broad range of industrial applications, including in food and detergent industries. Proteases from Bacillus sp. are a highlighted group of enzymes, since it presents good activity and stability. The xanthan gum produced by fermentation of Xanthomonas campestris is used in the food and pharmaceutical industries as a thickener and stabilizer. One of the problems in obtaining purified xanthan gum is the difficulty of separation of X. campestris cell mass by centrifugation due to high viscosity of the culture broth. The aim of this study was the characterization of protease from a strain of Bacillus licheniformis and its application in the clarification of culture broth of X. campestris. The protease extract from B. licheniformis was partially purified using Sephadex G-100 gel chromatography and crude and partially purified protease were characterized using response surface methodology (RSM). The two protease preparations showed optimal activity at pH 7.5 and 55°C and considerable stability in the range of pH 5.7 – 9.3 after 1 hour incubation at 30 – 36°C, presenting above 95% of residual activity. The crude and partially purified protease retained more than 78% of residual activity after 1h incubation at pH 7.5 and 50°C. The application of crude and purified protease preparations in the clarification of X. campestris culture broth was optimized using RSM and the best results of cells lysis and clarification of culture broth were obtained using 42 U of proteases/mL of cell suspension after 2h incubation at 60°C.