In developing countries eGovernment projects sustainability is being considered as new parameter for development across the world. Though strategic guidance is available from various agencies to overcome its associated challenges and have its smooth implementation, however developing countries doesn’t reflect much progress. The study conducted in this paper has made an attempt in collating pivotal role citizen plays in sustainability of eGovernment projects. Conceptual model prepared consists of eminent factors and once responses are collated at regular frequency it contributes in important decision making for policy makers and top management. The case study of an eGovernment Project- Income Tax have been included as part of paper and their transformation in delivery of services through ICT platform has been evaluated from sustainability perspective. In this study a model has been created as Government-Citizen Participation model for sustainable eGovernment projects for developing countries coupled with demographic conditions. A questionnaire has been distributed to 550 respondents and valid data for 450 respondents could be collected. The valid data is then empirically validated for model prepared in Indian context using PLS. The model prepared could be used in identifying the gap areas and taking appropriate steps well in time as per the project stage for similar studies in this context.