Officials in Shenzhen, China, will fine public toilet users 100 yuan (£10;$16) if they are deemed to have failed to urinate accurately in city facilities.
New laws that come into force next month in the southern city do not specify what amount of spilled urine would be classed as a violation.
The move has provoked derision and debate in local newspapers and on China's version of Twitter, Weibo.
Critics suggested toilet inspectors would be needed to enforce the rules.
The regulations were designed to curb the "uncouth use of a public toilet", a city government official told the AFP news agency.
The Beijing Times carried a commentary calling into question the necessity of making a law on something that could "be simply guided by social consensus".