Tanui who has been holding the position in an acting capacity since May last year, will serve for the next three years.
Tanui took over from Selest Kilinda, who was dismissed over allegations of nepotism by influencing the hiring of his two sisters and a brother at the company.
Prior to the appointment in an acting capacity in May, Tanui was Chief Manager Finance and Strategy, ICT, Business Development and Corporate Planning Departments at the corporation.
Before joining KPC, he was the head of finance at Kenya Tea Packers Limited (KETEPA) for a period of five years.
He has also worked at Nairobi Java House as Finance and Administration Manager, Kenya Airways, Sovereign Group and PFK Certified Accountants.
Tanui holds a Bachelors of Arts in Economics and Sociology and an MBA in Strategic Management from Moi University.
He is also a Certified Public Accountant (CPAK) and Certified Public Secretary (CPSK) and has attended several international trainings in Financial Management, Strategic Planning, Corporate Governance and Supply Chain Management.