Sardiha is an important panchayat in Saharsa District. The present work describes a report on the physico-chemical studies of drinking water of Sardiha, Saharsa, Bihar and its some interior area. Because of the geographical isolation and flood affected, people residing in the interior area, mostly do not have access to safe drinking water. In the absence of fresh water supply, the people are forced to take water from any source that lies in the village. In most of the interior area, tube wells water is used for drinking purposes and other domestic purposes. Tube wells water is the underground water and is generally of good quality. Physico-chemical studies such as temperature, pH, dissolved oxygen, total dissolved solids, chlorides, total alkalinity, calcium hardness, iron, fluoride and nitrate of tube wells water was carried out from different sampling stations and compared with the standards values prescribed by BIS, ICMR, WHO and APHA. Results show that the amounts of iron present in drinking tube wells water is above the prescribed limit whereas other parameters are within the prescribed limits. Alkalinity of one tube well water is much higher, which is not fit for irrigation purposes.