Often referred as Government to Citizen (G2C) e-government services, many governments around the world are developing and utilizing ICT technologies to provide information and services to their citizens. In Saudi Arabia (KSA) e-government projects have been identified as one of the top government priority areas. However, the adoption of e-government is facing many challenges and barriers including technological, cultural, organizational which must be considered and treated carefully. This paper explores the key factors of user adoption of e-government services through empirical evidence gathered by survey of 460 Saudi citizens including IT department employees from different public sectors. Based on the analysis of data collected the researchers were able to identify some of the important barriers and challenges from these different perspectives. As a result, this study has generated a list of possible recommendations for the public sector and policy-makers to move towards successful adoption of e-government services in Saudi Arabia.