The commissioner's job "is an innovation that should be copied by other governors," he added.
He "wants to always make the people happy. That's why he has created a ministry for that purpose."
The remote Himalayan kingdom of Bhutan is known for measuring its success by Gross National Happiness rather than Gross Domestic Product.
Criteria taken into account include psychological well-being, health, education, vitality in the community and the living standards enjoyed by the population.
Okorocha, a leading member in President Muhammadu Buhari's All Progressives Congress party, is one of Nigeria's best-known but also controversial state governors.
He has been accused of appointing family members and cronies to government offices without regard to the state's lean finances, including naming his son-in-law as chief of staff.
In recent months he has honoured Liberia's outgoing President Ellen Johnson Sirleaf and South Africa's Jacob Zuma with statues in the state.
Zuma's statue was reported to have cost 520 million naira ($1.4 million, 1.2 million euros).
Okorocha was criticised for the expense as public sector workers in Imo were owed several months' salary.
He has also been criticised for spending millions of naira to put up a Christmas tree reputed to be one of the biggest in the world.