The interaction of grain boundaries (GBs) with inherent defects and/or impurity elements in multi-crystalline silicon plays a decisive role in their electrical behavior. Strain, depending on the type of grain boundaries and defects, plays important role in these systems. Here, correlation between the structural and electronic properties of 3{111} Si-GB in presence of interstitial oxygen impurities have been studied from first-principles framework considering global and local model of strain. We observed that the distribution of strain along with the number of impurity atoms modify the energetics of the material. However, the electronic properties of the considered Si-GB are not particularly affected by the strain and by the oxygen impurities, unless a very high local distortion induces additional structural defects.