Energy crises is the one of the major problem that was faced by Pakistan in order to overcome on that crises Pakistan need to be developed and improvement in energy sector, Throughout in the country the demand of water and power increasing day by day therefore hydropower project are the need of the hour in Pakistan. Before initiation of any project EIA play important role in evaluating the nature of the project on different factors. Government of Pakistan planned one of the mega hydropower project diamer basha dam was planned in Gilgit Baltistan. It was intended to conduct the research work on describing significant factors so as to evaluate the influence of the project on them and develop guidelines for environmental assessment for these factors. To find out these significant factors the methodology was adapted to conducting field investigation. Besides to assess the relevant impact questionnaires were developed. Finally, in order to reduce the negative impact of the project on the predefine factor mitigation measure was suggested. It is anticipated that this study work support in developing structure work to be executed as mitigation measures and boost the advantages of the project.