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.
He retired from the provincial administration in 1998.
In 2002, he was nominated to Parliament and in 2007, he was elected as the Member of Parliament for Ijara Constituency on a Kenya African National Union (Kanu) ticket.
At the time of his death, Mr Haji was serving his second term as the Garissa senator.
Uhuru, leaders eulogise Haji
President Uhuru Kenyatta is among Kenyans who have condoled with the family and the people of Garissa County following the death of their senator.
In his message of condolence, the President eulogised the veteran politician as a dependable Kenyan leader and patriot.
“It is very unfortunate that we have lost such a dependable, solid and highly accomplished Kenyan leader.
"Mzee Haji was a highly respected leader and elder whose wisdom, deep knowledge of the Kenyan society and long experience as a public administrator enabled him to serve the country in various leadership roles with distinction for many years," the President said.
The President said the death of Senator Haji is a big blow to the country, especially for the Building Bridges Initiative (BBI) constitutional reform process where his leadership will be dearly missed.
"Mzee Haji was a steward of the BBI process and a strong pillar of our desire to construct a cohesive, peaceful and more progressive Kenyan nation. His stewardship of the initiative shall be missed," the President added.
Other leaders who sent their messages of condolences include Deputy President William Ruto, Garissa Township MP Aden Duale, Nominated Senator Abshiro Halake and Governor Wycliffe Oparanya among others.
DP Ruto mourned Mr Haji as a gifted politician who had ground-breaking mediation skills.
He said the country has lost a devoted and indefatigable administrator.
The country has lost a devoted and indefatigable administrator who was cause-driven. Senator Mohamed Yusuf Haji was a gifted politician, modest yet strategic schemer with ground-breaking mediation skills. pic.twitter.com/5FBLZHaaax
On her part, Ms Halake said Mr Haji was dedicated to serving his country with distinction.
2/.2 May Allah grant him Janatul Firdaus & give his family, friends, the people of Garissa and the entire country comfort during this difficult time. Baba had a remarkable life, rich in family and friends and dedicated to serving his country with distinction. Rest in peace Baba. pic.twitter.com/p63ySlQl3S
And Mr Duale said Garissa County will miss Senator Haji’s guidance, terming him a man who advocated for peace and harmony among the pastoralist communities.
Garissa in particular will forever miss his guidance. He was a man who advocated for peace and harmony among the pastorals commuinities during his lifetime.
At a personal level, He was my father, my senator, political mentor, adviser and above all, leader of my community.
Governor Oparanya said Mr Haji was hands-on and focused public servant who served Kenya diligently. He said the Garissa senator will be remembered for his contribution and leadership as the chairman of the BBI taskforce team.
Senator Mohammed Yusuf Haji was a dedicated, committed, hands-on and focused public servant who served this country diligently in different capacity.
He will be remembered for his contribution, wise counsel and steadfast leadership as chairman of the BBI taskforce team. pic.twitter.com/UABZTDxCbj