Abstract: Infections caused by beta lactam antibiotic resistant bacteria are common in hospitals and community and continue to be a major cause of morbidity and mortality worldwide. Hence, rapid laboratory diagnosis is necessarry to counter the effect of these bacteria. Several tests have been developed for screening for beta lactamases bacteria. The aim of the present study was to compare the validity of two tests used for this purpose. Staphylococcus aureus, Streptococcuspyogenes, Bacillus subtilis, E.coli and Klebsiellapneumoniae were isolated from different clinical samples from Azadi teaching hospital, Kirkuk, Iraq and screened for beta lactamases production by antibiotic disk diffusion test and iodemetric test. Both tests seem to have same reliability when screening for penicillinase producing bacteria. However, when cephalosporin resistance is concerned, antibiotic disk diffusion test is recommended.