Mayor Bill de Blasio has taken the concept of a Nanny State to a whole new level — instructing New Yorkers about what they can and cannot flush down their toilets.

“New York City: There are only FOUR things that should go in your toilet,” the mayor’s office tweeted from its official account Tuesday.

Below the edict is an emoji of a porcelain throne followed by an anthropomorphic “poop” emoji, three droplets of water for “pee,” a queasy green face for “puke,” and a hand making a wiping motion for “toilet paper.”

“Everything else causes FATBERGS!” the tweet warns.

“What are Fatbergs? Well, you gotta click on FatbergFree.nyc,” it reads.

The link leads to a public service video about clumps of cooking grease, wet wipes and “lots of other stuff” including tampons and Q-tips that clog up city sewers when they’re flushed down toilets.

A Department of Environmental Protection spokesman called fatbergs a “growing problem” that costs New Yorkers $19 million annually.

“They clog the sewers and machinery at the city’s wastewater facilities,” DEP spokesman Edward Timbers told The Post.

He also forwarded a photo of a fatberg longer than 10 feet pulled from the city sewer system by a crane.