Jennifer Lopez Makes Vegas Deal ... Better Than Britney's

Jennifer Lopez is in the final stages of making a deal to perform in Vegas ... and according to the contract -- obtained by TMZ -- she'll rake in more per show than Britney Spears.

Jennifer is being offered a whopping $350K per show at The Axis at Planet Hollywood ... the same place Britney is performing.

Britney is making a paltry $310K a show.

But Britney will ultimately score more than JLo because her contract provides she'll do 96 shows over 2 years. JLo will do 72 shows, 3 times a week for 24 weeks over a 1 or 2 year period -- the contract leaves that open.

So, in the end, Britney is guaranteed $29,760,000 for the 2-year run. JLo will be guaranteed $26,383,326.

It's all chump change compared to Celine Dion ... who does 70 shows a year and gets $33,320,000.