Water is the most important substance in our daily life. Without it, life would not have been possible. Potable water is essential to humans and other life forms, as water is important to the mechanics of biological metabolisms in the body. Drinking water should be pure and free of contaminants to ensure proper health and wellness. Drinking water from different water resources such as wells and tankers should be free from contamination with waterborne pathogens including bacteria, fungi, viruses and parasites.Treatment of water using many ways is generally done in order to purify it.However, some water treatment techniques may not properly handled. In addition, water transferring techniques may contaminate the drinking water. Therefore, this study was aim toinvestigate drinking water in wells and tankers to observe any microbial pathogen presence as a source of health hazard.One hundred and eightwater samples from different sources were examined for microbial pathogens using filtration method on solid and liquid selective media. Four sources include sea desalinated water(SDW) from governmental water desalination factories, drinkable wells water (DWW), non-drinkable wells water (NDWW) and commercial desalinated water(CDW)from small commercial water desalination factories.Seven DWW samples (58.3%) and five NDWW samples (41.7%) were contaminated with E. coli. Eleven DWW samples (91.7%) and all NDWW samples (100%) were contaminated with P. aeruginosa. One DWW sample (8.3%) and twoNDWW samples (16.7%) were contaminated with E. faecalis. Four DWW samples (33.3%) and one NDWW sample (8.3%) were found contaminated with aspergillus spp. Four SDW samples (100%) and four CDW samples (50%) were contaminated with Penicillium spp. Conclusion:CDWwas found to be the more suitable than other sources for drinking if a biological hazard is the main target. However, contamination at transferring process should be addressed. Yet, water tanker which is a common transferring technique in many areas in Saudi Arabia and should be tested for safety level from point of contamination hazard during the transferring process.