A preliminary test concerning variabilities of some Tomoceridae species of collembola has been made using scanning electron microscopy and enzyme analysis. No definite taxono mical characters were detected in the integument of 6 species belonging 4o 2 subgenera of Tomocerus genus. The zymograms obtained by electrophoresis, however, revealed that the subgeneric characters at times should be questioned. for its monophyletic meaning as suggested by those of Tomocerus (Tomocerus) kinoshitai showing a particular pattern and Tomocerus (Tomocerina) liliputanus for its apprectable variability. The distinctive zymograms of T. laxatamella might also justify the creation of a new subgenus when considered in combination with the morphological characteristics of mucron. Neither populational nor interspecific differences were observed, however, in and between T. cuspidatus and T. ocreatus, which would remain problematic and necessitate further works to confirm. Tomocerus laxatamella and T liliputanus showed more or less variabilites whereas Homidia koreana of Entomobryidae, used as out-group for comparison, displayed a prominent individual variations in a few loci.