Poor performance of construction projects is one of the major cause for concern in the construction industry. Many of the construction projects executed in Nigeria experienced several challenges ranging from simple to complex issues. This paper therefore, examines factors affecting the performance of construction projects, their effects on the economic development and the impact of the factors on the economic development of the nation. The study identified a set of factors believed to affect project performance through extensive review of literature which form the basis for questionnaire survey. A total of 200 questionnaires were self-administered to professionals in the Nigerian construction industry, out of which 148 were retrieved and considered fit for analysis. The survey findings indicate that the most important factors affecting project performance are: project design cost, project complexity, unavailability of resources, quality of equipment and raw materials, while ontime completion, client satisfaction and productivity were considered to be the main measures of construction project performances. Improvement in technology and extension of infrastructures, were the most important indices of economic development. It is recommended that project owners must work collaboratively with all the professionals involved in carrying out construction project in order to facilitate good performance. More so, stakeholders in the construction industry including professionals and regulatory bodies should be proactive in discharging their responsibilities bearing in mind the effect of construction project performance on economic development of the country. .[email protected].