This study develops and validates a model to predict internet users' intentions to buy online, based on an extended technology acceptance model (TAM). We proposed that in addition to technology's ease-of-use and usefulness, compatibility with technology, and perceived risk are considered as determinants of customers' attitude and intentions toward on-line shopping. The data was collected from 931 internet users. Results show that: 1 customers' attitude is determined by compatibility with technology and perception of its usefulness and easiness, and negatively determined by technology's risk perception 2 customer's perception of usefulness is mainly predicted by compatibility with technology, followed by perceived risk and easiness of technology 3 customers' intention to buy online is positively determined by attitude towards online shopping and beliefs of its usefulness and negatively determined by perceived risk of technology. Finally, several implications of the findings are discussed and directions for further research are provided.