Given the lack of information on the resistance to betalactams conferred by the bla(ROB-1) gene in our area, we decided to undertake a study to determine if and how often it appears in our isolates. We analyzed the presence of the gene in 177 strains of Haemophilus influenzae and compared the results with those from the biochemical tests (nitrocefin). Sixty-three strains tested positive in the nitrocefin test (35.6%). The presence of the bla(ROB-1) gene was detected in seven of the 177 strains (3.9%). All the strains expressing the gene also tested positive in the nitrocefin test. Of the 63 strains that showed biochemical resistance (positive to nitrocefin), seven were found to be caused by the presence of the bla(ROB-1) gene. An epidemiological follow-up for the presence of this gene in our area is therefore advisable.