This paper reports on an examination of the impact of knowledge sharing on product and process innovation. In it we try to identify the similarities and differences between these impacts in public and private Higher Education (HE) Institutions in Iraq. A mixed methods approach was conducted using 486 valid responses to test the causal relationships between knowledge sharing, and innovation. Then a qualitative approach was used to give more insight of the findings from the quantitative stage regarding the differences in the effect of the studied relationships. Employing structural equation modelling, the research found that knowledge sharing plays a pivotal role in enhancing innovation in both sectors. The multi-group SEM and the interviews revealed differences between Iraqi public and private HEIs. Guidelines are developed for researchers as well as leaders, and evidence support using knowledge sharing to enhance innovation within HE in developing countries. The findings and suggestions for future research are discussed.