High tomato losses in the fruit supply chain can be prevented by use of improved or new technologies but these are not usually adopted where adoption behavior is barely known. Based on the Theory of Planned Behavior and the Technology Acceptance Model, this study analyses socio-psychological factors that influence the adoption behavior of traders on new postharvest handling technology, as exemplified by the use of lining material for improving tomato packaging in Tanzania. The study results conclude that the perceived behavioral control and subjective norm were the most important factors explaining respondents’ behavioral intention. Attitude, though found not to be a significant determining factor, was however significantly influenced by perceived usefulness and perceived ease of use. As technology adoption is a prerequisite for structural transformation of developing economies, our results provide new insights in the field of behavioral acceptance research in the tomato production sector of relevant developing countries.