The minimum inhibitory concentration of cefcanel, a new oral cephalosporin, has been determined for 182 clinical isolates, of which 84 were from the family Enterobacteriaceae, 45 were from the genus Streptococcus, 18 were nonfermentative rods, 25 were Haemophilus influenzae and 10 were Branhamella catarrhalis. In general, cefcanel was more active than the other cephalosporins against the species Escherichia coli, Klebsiella aerogenes and Proteus mirabilis. Among the genus Streptococcus only the enterococci were resistant to cefcanel. H. influenzae and B. catarrhalis showed also a reasonable susceptibility towards cefcanel. Oxidative rods were highly resistant to cefcanel.