Understand the uncertainties and evaluate the opportunity are essential to support the number of new businesses launched every day. The aim of this paper is to analyse the uncertainty factors related to the evaluation of opportunity in software entrepreneurship. This study is concerned with developing a simple and effective framework for software entrepreneurs to evaluate opportunities for their projected venture and predict its success in an uncertain environment. The paper begins with identifying uncertainty factors relevant to software start-ups. Then, we introduce the Opportunity Evaluation Model to evaluate the scope of opportunities as moderated by the uncertainties using External Factor Evaluation (EFE) and Internal Factor Evaluation (IFE) matrix methods. The model outputs Internal-External (I-E) matrix containing graphical representation of the opportunity position, with the strengths, weaknesses, opportunities and threats identified from the inputs. Two case studies with different factor ratings for uncertainties are demonstrated using the model with a detailed explanation of the procedure of implementation. The article ends with a note on the efficacy of the framework and reiterates the importance of research examining opportunities in relation with surrounding uncertainties. Early recognition and management of uncertainties identified in this paper can increase the chance of success for new software ventures.