The governor assented to the bill at the Lagos House on Monday.
This is coming 11 days after the State House of Assembly passed the bill that prohibits open cattle grazing in the state.
After passing the bill on September 9, the Speaker, Mudashiru Obasa commended his colleagues for their passion to see that the state continues to grow.
The issue of open-grazing has been a sensitive one in the country as it has created a rift between the southern governors and pastoralists.
As part of measures to contain the killings, the southern governors met in Lagos on July 5 and had far-reaching conclusions on open grazing, restructuring Nigeria, and calls for state police.
After the meeting, the Chairman of the Southern Governors Forum, Rotimi Akeredolu, said the governors agreed on a deadline for the promulgation of anti-open grazing law among its member states