Two teenage girls who wrote their names in red hairspray in Piccadilly Gardens were ordered to clean up the mess by police.
The girls, both aged 14, daubed onto the steps leading to the grass area on Sunday afternoon.
Large red writing could be seen scrawled on the concrete.
But officers caught the girls in the act and came over to reprimand them.
The two officers arranged for water, cloths, mops, buckets and brushes so the girls could clean up their own mess.
Biffa and the nearby Caffé Nero provided cleaning supplies for the teenagers.
A statement on the Greater Manchester Police City Centre Facebook page, written by Inspector Jon Middleton, said: "Yesterday afternoon two 14-year-old girls decided to graffiti their names onto steps in Piccadilly Gardens with hairspray.
"They were seen by officers who arranged for water, cloths, mop, bucket and brush for them to clean up their own mess (thanks to Café Nero & Biffa for the supplies).
"Before anyone complains there was nothing more serious going on in the gardens for the officers to deal with at the time as all was unusually quiet."
Dozens of people have commented to praise the officers for their actions.
Facebook user Edmund Wharram wrote: "Excellent. A few more Police forces need to take this approach."
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Gillian Moore commented: "So glad you made them clean it up hopefully they will think twice before they do it again."
Leigh Cable posted: "Good for them, restorative justice used right."
