The public sector continues to be under intense pressure to improve its innovation performance. Consequently, stakeholders are calling for more empirical studies on the antecedents of innovation, especially from a developing country’s perspective. Motivated by this call, we investigate the impact of institutional creativity and institutional innovation capacity on public innovation performance in the context of Ghana. Key to our model is that, institutional creativity and institutional innovation capacity are also enabled by inter-agency collaborations, institutional leadership, and stakeholder pressure. The partial least squares structural equation model is employed to estimate the survey responses of 195 respondents from fifty public sector institutions. The empirical analysis confirms that organizational creativity has a positive and significant impact on innovation performance, innovation capacity has a negative and insignificant impact on innovation performance, and inter-agency collaboration and institutional leadership contribute positively to institutional creativity and innovation capacity. However, stakeholder pressure negatively impacts both institutional creativity and innovation performance. This study contributes to knowledge on the antecedents of public innovation performance from a developing country’s perspective. It also advances theories on public innovation performance.