Procurement of construction projects in Nigerian Federal Universities has been affected by unethical procurement practices amongst the stakeholders and projects parties concern. This study aims at developing a framework to mediating the large negative effects of unethical procurement practices on construction projects development. Conflict of interest factors, especially at the tender and bid evaluation stages, were identified as the major unethical practices affecting construction procurement processes of infrastructure projects negatively. Data were collected using a survey questionnaire distributed to construction procurement stakeholders of nine randomly selected Nigerian Federal Universities. Mediation effect of ethical procurement practices was tested between the conflict of interest factors and procurement of construction and infrastructural projects. The findings revealed that conflict of interest factors were found to have large negative effects on procurement of construction and infrastructural project, and ethical procurement practices identified and introduced as mediating variables were tested and verified to possibly mitigate the effects of conflict of interest factors affecting the procurement of construction and infrastructural projects in Nigerian federal universities. Hence, the study recommends that procurement entities concern should ensure compliance with Public Procurement Guidelines (PPGs), which highlights ethical requirements for tendering, bid evaluation and construction processes for the procurement of construction and infrastructural projects.