According to family members, the senator was flown to Turkey in December and returned to the country on Saturday night and admitted to the hospital.
In September last year, the legislator underwent a five-hour operation at the same hospital after he slipped and dislocated his hip while at home in Garissa.
Mr Haji was the chairperson of the Building Bridges Initiative (BBI) task force and is the father of Director of Public Prosecutions (DPP) Noordin Yusuf Haji.
Mr Haji joined Kenya’s provincial administration in 1960 as a district officer (DO) and rose through the ranks to become one of the country’s most powerful provincial commissioners.