Twenty fife Isolated of Porteus mirabilis were collected taken from different human infection and diagnosed by API 20E TEST. These isolated tested for their resistance to Ampicillin, Tetracycline, Chloramphenicol, Streptomycin, Cepfaloexin, Naldixic acid and Trimethoprime, then classified into 6 groups according to antibiotics resistance. In order to remove their antibiotics resistance in these studied isolated, the chemical substance urea and physical agent heat at 44 ْC were used. Then combined the effects to these to agents also used the results revealed that the urea cause remarkable curing of most antibiotics resistance at concentration 400 µg/ml, were the percent of colonies that lose their antibiotics resistance range (18-92). In addition, curing by heat at temperature 44 ْC was carried out and the results showed that this agent appear to be more efficient than urea in curing the Amp and Cm resistance. The combined effects of urea and heat at 44 ْC does not show any increasing in curing percents. Finally no curing for the resistance of Streptomycin and Trimethoprime which may indicate that gene for conferring these resistance located on the bacterial chromosome of P. mirabilis isolated and this leads that no effects of the used of curing agents on antibiotics resistance genes located on chromosome.