The remark is said to have been written on the Norwich City FC Fan Club Facebook page after the Canaries suffered a 4-1 defeat at the hands of Arsenal on Saturday.
According to the Daily Mail, a spokesman for Norfolk Police said: "We can confirm that we have received reports of a racist remark posted on a Norwich City fan club site and police are investigating. The comment has since been taken down from the site.
"Norfolk Constabulary takes any incident of hate crime very seriously. No incident is seen as trivial, and any report is investigated thoroughly. Norwich City Football Club has been informed."
Hughton was allegedly racially abused on a separate Facebook page earlier this month.