Sri Lanka appointed Ford first in 2012 and after two years in charge, the 55-year-old moved to Surrey, whom he led to promotion from County Championship Division Two last year.
"...Graham Ford will rejoin Sri Lanka Cricket as the Head Coach with effect from 1st February 2016," the country's cricket board said in a statement.
"He will be entrusted with the national team for a period of 45 months to build the strength and stability of our cricket until the ICC World Cup in 2019.
"His main task would be to enhance the capabilities of the young national team which is currently on a rebuilding process," the board said, referring to the team currently going through a transition since the retirement of batting stalwarts Kumar Sangakkara and Mahela Jayawardene.
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The head coach's position has been lying vacant since former test captain Marvan Atapattu resigned in early September.
"As the national team continues its transition following high-profile retirements, Ford's reputation for being good with young players was among the reasons... to secure Ford for the job," SLC added.
Ford was South Africa's coach from 1999 to 2001 before moving to English county Kent as director of cricket in 2004. In 2006 he returned to South Africa to take charge of the Dolphins.
Surrey director of cricket Alec Stewart thanked Ford for working "tirelessly" to help the club's return to First Division.
"It was a very tough decision for Graham to leave Surrey but we understand that the opportunity to go back and coach at International level with Sri Lanka was too good to turn down."
(Writing by Sudipto Ganguly in Mumbai; editing by Amlan Chakraborty)
