Before we start make sure that your OnePlus Two bootloader loader is unlock if not then follow this tutorial to
1.How to Unlock Bootloader of Oneplus Two.
2.How to Install Custom recovery in OnePlus Two
#How To Root OnePlus Two
1.Firstly you need to download SuperSU.zip.And Palce it some where in you device.
2.Enter TWRP recovery via the advanced power menu by pressing ( power + volume down)button.
3.Now Select the install option from the TWRP recovery.
4.Navigate to where you have SuperSU stored on your sd card and select it.
5.Then Swipe to install the recovery.
6.Once you’ve installed SuperSU hit
the back button, and hit the reboot system button.
7.Done!Now you will see Super Su app in your App drawer it means You have successfully rooted OnePlus Two !That’s it.