Social capital plays a significant role in post-disaster community participation and disaster recovery. This study divides social capital into three aspects: Cognition, structure, and relation, and discusses the impact of these factors on community participation in post-disaster recovery. Through data analysis, we found that a self-organized relationship villager network had a positive effect on villagers’ participation in voluntary community activities after an earthquake, while the local cadre relationship network had a negative impact. However, the latter could encourage villagers to participate in disaster-recovery activities organized by the local government. These findings indicate that the mobilization mechanism for post-disaster local-government reconstruction and community self-organization are the same, both coming through the social-acquaintance network, a type of noninstitutionalized social capital. The implication of this study suggests that local government should attach much importance to the construction and integration of social networks in earthquake-stricken areas to cultivate community social capital.