The method of differential staining of muscles and connective tissue in the genitourinary organs (urinary bladder, ureters, renal pelvis) and gastrointestinal tract is suggested. The method consists of the intermittent use of known tissue van Gieson dyes (picric acid and fuchsin). When applied at pH = 7.2-8.0 (phosphate or citrate buffer) they stain the connective tissue in red and muscles in gold-yellow colour. A saturated solution of picric acid was mixed at equal proportions with water-free glycerol. Fuchsin was taken as 0.3% buffered solution or as 1% solution applied on the organ intermittently with picric acid. The organs, before staining, are fixed in 0.3 alcoholic solution of carbonic acid.