Abstract: Yemen is facing a number of economic challenges and the performance of its government institutions is inefficient. However, internet technology usage can help redress some of this and play an important role in encouraging economic growth, improving institutional efficiency and enhancing employee performance. Many theories and models have been developed and proposed in the Information System (IS) context in order to predict and explain user behavior with technology. In this respect, DeLone and McLean Information Systems Success Model (DMISM) is one robust model for evaluating Information Technology (IT) through user satisfaction and net benefits and it has become widely used to measure the success of information systems. However, while DMISM is both robust and effective it neglects to focus on task-technology fit construct the degree to which the system fits with tasks and needs. In the context of technology usage within organizations, actual usage and user satisfaction are not enough to provide a full picture without taking into consideration whether the technology fit with tasks or not, something considered highly imperative when studying technology usage within organizations. So, this study applies DMISM as the underpinning theory but extends it with a construct task-technology fit. It also takes s further step forward in order to increase the power of explaining the model’s output by examining the net benefit construct through four different variables, namely process, knowledge acquisition, communication quality and decision quality. A survey questionnaire was used to collect primary data from 530 internet users among employees within all 30 government ministries in Yemen. An analysis was conducted to examine the relationship between the variables of the proposed model including Confirmatory Factor Analysis (CFA) and Structural Equation Modeling (SEM) via. AMOS. The results of the data analysis showed that the data fit the extended DMISM model well while the findings of the multivariate analysis demonstrated four main results: first, system quality and information quality have a great influence on actual usage, user satisfaction and task-technology fit; second, actual usage has a positive impact on user satisfaction, process, knowledge acquisition and communication quality; third, user satisfaction positively influences process, knowledge acquisition, communication quality and decision quality and fourth, task-technology fit significantly influences process, knowledge acquisition and communication quality. The proposed model explained 72% of the variance in the process, 45% of the variance in knowledge acquisition, 46% of the variance in communication quality and 15% of the variance in decision quality. The theoretical and practical implications are discussed and this study concludes by discussing the limitations of the study which should be addressed in any future research.