Abstract : Cost estimation is one of the crucial tasks handled in the project initiation phase and has a great effect on project performance. Ministry of Youth and sports (MYS) in Kingdom of Bahrain had indicators that support the possibility of having construction cost estimation deficiency problems. The problem to be investigated in this research is the inaccuracy of cost estimate of MYS construction projects. The main objectives of this research are to assess the level of cost estimation accuracy in MYS construction projects, identify the factors affecting the current cost estimation in MYS projects and develop a cost estimation model that enhances the cost estimation process. The objectives of the study are achieved through a comprehensive literature review about the three main issues: level of cost estimation accuracy, factors affecting cost estimation accuracy and developing a model for cost estimation. The data collected to achieve these objectives are actual construction projects data executed by MYS and questionnaire survey information collected from stakeholders who worked with MYS. The cost estimation model developed using two combined techniques: partial least square structural equation model (PLS-SEM) and artificial neural network (ANN). The application of PLS-SEM on the critical factors determined by the participants provided theoretical support for the study conceptual framework. While ANN modeling identified the influential factors affecting MYS construction cost estimation. This research provides an insight into the current cost estimation level in MYS, which provides opportunities to improve the cost estimation during the projects design phase. Also, the relationships between the research variables: availability of cost estimation unit; information quality; estimator performance; project characteristics; external factors; and contractual procedure on the construction cost estimation accuracy have been confirmed. The study suggests the need to control the highest-ranked factors: information quality, estimator performance and project characteristics to enhance the cost estimation process efficiency.