The experiment was conducted to evaluate the shelf-life of normal and heat treated yoghurt (dahi) at room (28.3 °C) and refrigerated temperature (5 to 6 °C). Normal dahi at room temperature was good upto 2.3±0.58 days but at refrigerated temperature it was good upto 7.3±0.58 days. Heat treated dahi at room temperature was good upto 3.3±0.58 days and at refrigerated condition it was in good condition upto 38.3±7.64 days. Physical tests showed that smell and taste; body and consistency; colour and texture deteriorated depending on storage time. Deterioration was rapid at room temperature in case of normal dahi samples. Chemical analysis showed that fat, protein, total solids and ash content did not undergo any change but significant difference was found in case of pH (P<0.01) and acidity percentage (P<0.05). In case of microbial count/g (log value) differences were found except yeast count (P<0.01) and significant differences were found in total viable (P<0.05) and mold count (P<0.01) except yeast just before spoilage (JBS) with increasing of storage time. It was found that normal dahi spoiled rapidly and heat treatment was an effective way to increase the shelf life of dahi.