NOVELTY - Production of sugar-lipid biological surfactant involves adjusting liquid fermentation culture medium to pH of 6-6.5, sterilizing fermentation culture medium, inducing Pseudomonas aeruginosa BQ11 (CGMCC NO.7674) strain, stirring, fermenting, when the content of fermentation liquid reaches to 8-10 g/l, then stop the fermentation; carrying out solid-liquid separation by removing thalli in the fermentation liquid to obtain red brown clear liquid; adding 60-120 mg/l diazanium sulfate in brown clear liquid, vacuum filtering, decompressing and concentrating the filtrate.    USE - For production of sugar-lipid biological surfactant (claimed), used in petroleum industry, for tertiary oil recovery; and in food industry, cosmetic, medical treatment.    ADVANTAGE - The process obtains sugar having stronger lipid surfactant and interface activity; has high selectivity and specificity; produces non-toxic or low-toxic and biodegradable sugar-lipid biological surfactant; and avoids environmental pollution.    DETAILED DESCRIPTION - Production of sugar-lipid biological surfactant involves adjusting liquid fermentation culture medium to pH of 6-6.5, sterilizing fermentation culture medium, inducing Pseudomonas aeruginosa BQ11 (CGMCC NO.7674) strain at constant temperature of 31 plus minus 1 degrees C, stirring at a speed of 180-220 revolution per minute (rpm), continuously fermenting for 72-76 hours, when the content of fermentation liquid reaches to 8-10 g/l, then stop the fermentation; carrying out solid-liquid separation by removing thalli in the fermentation liquid under the pressure of 0.1-0.2 MPa to obtain red brown clear liquid; adding 60-120 mg/l diazanium sulfate ((NH4)2SO4) in brown clear liquid at 4 degrees C, standing for 10 hours, vacuum filtering to remove protein precipitate, collecting the filtrate at 40-45 degrees C, decompressing and concentrating the filtrate to 40-45 vol.% by volume to obtain the sugar-lipid biological surfactant as brown concentrated liquid. The liquid fermentation culture medium comprises 5-8% glycerin, 2-2.5 g/l sodium nitrate (NaNO3), 2.5-3 g/l diazanium sulfate ((NH4)2SO4), 0.5-0.8 g/l magnesium sulfate heptahydrate (MgSO4.7H2O), 2-2.5 g/l potassium hydrogen phosphate (K2HPO4), 2-2.5 g/l potassium dihydrogen phosphate (KH2PO4), 1-1.5 g/l sodium chloride (NaCl), 0.1-0.2 g/l calcium chloride dehydrate (CaCl2.2H2O), 0.1-0.2 g/l ferrous sulfate heptahydrate (FeSO4.7H2O), 1-1.5 g/l yeast extract, and rest water.