Unlike previous PlayStation consoles, the Sony PlayStation 3 was built for support of more than 2 controllers. In fact, the PS3 can recognize up to 7 wireless Bluetooth controllers. While there is no sync button as there is with the Xbox 360 and Wii, connecting multiple PS3 controllers is quite easy if you follow these steps.
Plug in the controller into the PS3 via the USB cable.
Turn on the PS3.
The controller will automatically sync with the PS3 and will be given a player number from 1 to 7, indicated by a red light on the back of the controller. If the sync does not occur automatically, press the PS button on the controller and the pairing will occur.
Once the controller is paired with the PS3, you can unplug the USB cable and use the controller wirelessly.
For player numbers above 4 the controller will light up 2 indicator lights and the sum of those 2 numbers indicates the player number.
Pairing a controller with a new PS3 will erase any previous pairings. To re-sync with another console, you will have to pair it again.