Dappy has had the small symbol, which is widely associated with the social networking site Twitter, etched underneath his right eye.
Last night, N-Dubz star Dappy showed off his new tat in a close-up selfie of his face, which he posted to Twitter.
Alongside it, he told his followers: "By the way, the reason I got a # Tatted on my FACE was simply 2 make sure IT stays trending 4 ever."
Dappy is a big fan of tattoos, although arguably this is his most bizarre to date. Even his fans have found it amusing...
One commented: "OMG, someone please tell me Dappy's hashtag tattoo is a joke. I can't cope."
It was also revealed last month that Twitter bosses are considering doing away with the hashtag symbol, which helps users search topics and see what is trending.
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