The microbiological quality of a sixty day ripened, on-farm manufactured, semi-soft, mixed coagulation cheese was evaluated. Samples from 42 cheeses were analysed for their aerobic mesophilic counts, lactic acid bacteria in three solid media (MRS Agar, M17 Agar and MSE Agar), yeasts and moulds, psychotrophs, Enterobacteriaceae, coliforms and faecal coliforms, coagulase-positive staphylococci, sulphite-reducing clostridia and Salmonella spp. The aerobic mesophile bacteria constituted the largest group of micro-organisms found. The largest number of lactic acid bacteria was obtained with MRS Agar; M17 Agar and MSE Agar gave similar counts although the latter was generally lower. The mean log cfu g-1 of psychrotrophic micro-organisms was 4·77 and for moulds and yeasts 4·30. Thirteen, 25 and 45·8% of the samples were found negative for enterobacteria, coliforms and coagulase-positive staphylococci, respectively. Sulphite-reducing clostridia, faecal coliforms and Salmonella was not detected. The mean pH of the samples was 4·07 ± 0·5. © 1992 Academic Press Limited.