The Twilight hunk is currently filming new film Cosmopolis in Canada, and has been spotted enjoying a fair few nights on the town while his girlfriend stays at home in the US and looks after his dog.
And according to Now! Magazine, he's been ordered to tone down his wild ways.
'Rob's been partying hard,' said an insider.
'He's been out almost every night at concerts and dinners with pals - and this is hot on the heels of him going out clubbing with Sienna Miller in London a few weeks ago.
'Kristen's upset about his partying and ended up having a tearful showdown with him over the phone, saying he's acting as if he finds life boring with her.
'She's feeling insecure because she's back home looking after their dog Bear and hasn't seen him for weeks.
'But Rob thinks she's blowing it all out of proportion.'