The microbial production of gluconic acid has been investigated using a mutant Gluconobactor oxydans GPM 60 through optimization of some Physical parameters. Production conditions like initial pH, incubation period, volume of media, age of inoculum, volume of inoculum, agitation and temperature were individually opitimized one by one. The maximum yield of gluconic acid is 13.80 g/L with pH 6.0, 96h incubation, 20 ml medium, 48h age of inoculum, 10 ml volume of inoculum, 250 rpm agitation and 30oC temperature.