Who win John Cena or brock lesner summer slam?

You're asking about a past event! To know who won the SummerSlam match between John Cena and Brock Lesnar, you'd need to specify the year. They have faced each other multiple times at SummerSlam.

Here's a breakdown of their SummerSlam encounters:

* 2014: Brock Lesnar defeated John Cena via submission.

* 2017: John Cena defeated Brock Lesnar via pinfall.

So, it depends on which SummerSlam match you're interested in!