Michael Bacall, who co-wrote the screenplay for the movie about three teenagers planning a raucous party to boost their popularity, is currently working on a treatment for the sequel.
Bacall started working on the sequel a few weeks before Project X premiered at cinemas across the US, according to The Hollywood Reporter.
The treatment will be handed over on completion to producers Todd Phillips and Joel Silver to decide if they would like to develop it into a script.
It is not yet known whether lead actors Thomas Mann, Oliver Cooper and Jonathan Brown would return for the second instalment.
Project X made a massive $20,775,000 (£13,206,000) in US cinemas this week. It also made the top 10 in the UK and topped the Australian box office in its first week of release.
Watch a clip from Project X below: