Recent penetration of Web 2.0 and social network services (SNS) seems to make information quality (IQ) in those services more important. The main objective of this research is to grasp the impact from system quality to dimensions of information quality and to analyze relationships among those qualities and intention to re-use in Web 2.0 services including SNS. Based on socio-technical approach, information quality research, the updated IS success model and the IS diffusion variance model, the structural equation model is constructed and empirically tested. The result shows that system quality positively affects both intrinsic IQ and contextual and representational IQ, and that the latter exerts more impact on intention to re-use than the former. System quality also positively affects intention to re-use. Researches for the impact from system quality to information quality are scarce, thus our research contributes to this topic. We also found that the role of technical compatibility and user interaction environment on system quality is important and there is little lock-in effect for Web 2.0 services. The result of this research suggests a strategy for practitioners of these services to keep their competitive edge and retain users.