Coliform bacteria are gram-negative Rod shape bacteria found in the intestines and stool of humans and warm-blooded animals. Among these, Escherichia coli is Fecal coliform bacteria are used as biological indicator to assess water quality. In this work used In this work used Most Probable Number (MPN) technique by culture medium and used Loop-mediated Isothermal Amplification (LAMP) method targeting the lacZ gene targeting the lacZ gene to detect E.coli and targeting the uida gene detect for coliform both reading the result by gel electrophoresis. All 30 water samples analyzed form drinking water tank inside the Prince of Songkla University. The result, according to the MPN method found to grow bacteria coliforms all 5 samples. In this 5 example there are 2 examples E.coli. Moreover after one month to repeat sample for examined in a sample exceeds the MPN. The positive sample were taken for analysis of coliform bacteria by LAMP. It found that all the tubes that were positive result by MPN method was able to detect by LAMP method as well as. The LAMP with high specificity and sensitivity to detect just 1 hour compared to MPN.