Lil' Kim wasn't seeing green in Poughkeepsie ... so she bailed!

Sources tell TMZ Lil' Kim's camp canceled a concert at the Mid-Hudson Civic Center in New York because she didn't get paid to perform. The show was originally slated for March 11th but was rescheduled for April 1st because the promoter couldn't sell enough tickets.

We're told management for the venue suggested a more cozy space, but the promoter was adamant about keeping it at the 3,000 person venue ... and he insists he did pay Kim a $5,000 deposit.

Kim's camp claims they never got any funds ... so instead, Kim chose to hang with the Kardashians in L.A. She's kinda been in the bff zone with Kim K since last week.