How can modify iBeacon 's UUID , Major,minor?

If you've set up an iOS device to behave as a beacon, you can set the IDs to wehatever you wish. You can't typically change the IDs of a beacon you don't own without the use of a library provided by the manufacturer. If there's no library available, beacon manufactures typically provide a companion app or web site for configuring the IDs in the beacons themselves.

-Mark

You should check the manufacturer's documentation on how to change the iBeacon's parameters.

There is no built-in API to accomplish this in iOS.