Leigh Griffiths cleared by Police Scotland over allegations of inappropriate messages
Police Scotland said there was "no criminality" after they carried out a "full assessment" following claims the 30-year-old sent improper messages to a 15-year-old girl, as well as another teenager, on social media.
Griffiths, who used to play for Hibs, was sent home from Celtic's pre-season training camp last week after officers began their investigation.
A Police Scotland spokeswoman said: "In relation to recent reporting regarding alleged inappropriate communications online, a full assessment has been carried out and it's been established there is no criminality."
Celtic took up a one-year option on the striker's contract earlier this month after his Parkhead future had been in doubt.
A spokesperson for the club said last week: “We have been made aware of online comments concerning Leigh Griffiths. The club will now look into this matter carefully.
“Leigh has left the club’s training camp as we do this."