The key of current supply-side structural reform lies in how to promote firm innovation. Using survey data of World Bank about institutional quality of Chinese enterprise operation, this paper test the effect of diversity in human capital structure on firm dual innovation. The results show that, skill diversity in production workers significantly reinforces firm exploratory innovation, but have no significant effect on firm exploitative innovation; gender diversity in production workers weakens firm exploratory innovation and exploitative innovation, but this effect is not significant; however, gender diversity in non-production workers has significant effect on firm dual innovation. Several robustness checks corroborate the findings. The findings of this paper enrich the literature on the influence factor of firm dual innovation, and it also provides implication to the firm human capital allocation and cultivation of labor market system in china.