Motivated by the research gap on intergenerational succession dynamics of family firms, this study examines the effects of initiating intergenerational succession on firms' innovation activities. We propose that initiation of intra-family succession can result in founder–successor co-governance that represents a strategic transition to the succession and incorporates the two conflicting yet complementary directions of change and continuity. Grounded in the theory of altruism, we suggest that co-governance will positively affect firms' innovation activities and that this positive link is contingent on the idiosyncratic intra-family relationships of kinship type, age difference, and gender difference between the founder and the successor. Furthermore, we posit that co-governance will lead to a flow of resources to low risk, rather than more inventive but higher risk, innovations. Based on the unbalanced panel data of 4,694 firm-year observations in our sample from listed Chinese family firms during the 2006–2015 period, empirical analysis supports our hypotheses and confirms that when examining family firms' innovation, there is a need to take the heterogeneity of the intra-family governance structure more fully into consideration.