The measure was backed by the Liberal Democratic Party, the largest voting bloc in the assembly.
"We need to deliver a strong message to the public to alter practices that have become so pervasive as to be perceived as custom," Shinichi Nakayashiki, chief of policy affairs of the LDP assembly group, told the Asahi Shimbun.
The ordinance, which takes effect Oct. 1, calls on escalator operators to ensure users are informed of the rule by posting signs.
The measure allows for the prefectural government to issue warnings to operators of escalators where users are seen violating the rule, but there are no penalties specified for violations.
A report by the Japan Elevator Association, an industry group, said there were 805 reported incidents of people being injured as a result of moving on escalators between January 2018 and December 2019.