Martin Scorsese Celebrates 81st Birthday with TikTok-Inspired Cake

Martin Scorsese has become a TikTok sensation in recent months -- and it looks like his family wanted to highlight that for his birthday ... with a sweet treat that's totally lit.

The famed director -- who's as old school as it gets -- hit the big 8-1 Friday ... and his loved ones threw him a little shindig to celebrate -- complete with a cake, of course, that was intricately decked out to reflect his viral stardom.

Check it out ... his 24-year-old daughter, Francesca, got some video of her dad's born-day pastry -- and it's full of Gen Z lingo that Marty's apparently pretty keen on.

The big icing writing across reads, "We Slay Birthdays" ... and other hip phrases like "Tea," "Slept On," "Throw Shade" and "Ick" are stenciled on all sides -- with a giant TikTok logo on top, of course.

Francesca certainly seemed impressed by the job that their cake decorator did on this ... and for good reason -- it's pretty freaking awesome. Papa Bear himself also looked pleased.

If you're unaware of what this is all about ... Francesca's been featuring MS on her TikTok videos lately -- and she's been having him use all the fun features, like voice-changers, and having him play viral games that all the young'ns are into ... including movie rankings.