The front (recto) contains parts of seven lines from the Gospel of John 18:31–33, in Greek, and the back (verso) contains parts of seven lines from verses 37–38.
I read somewhere that P52 dates back to 125 AD or earlier, and that it was discovered in upper Egypt. This means that the Gospel of John had been copied and was being read far beyond the borders of Israel by the beginning of the 2nd Century