There’s a simple workaround to root your Asus Transformer TF300T tablet and the following guide explains it. Follow the steps given below and you will end up with a rooted Transformer tablet.
I. Before You Begin:
1. You must have ClockworkMod Recovery installed on your tablet. You can do it from here.
II. Downloading Required Files:
1. Download the Rooting Package from here.
III. Rooting Asus Transformer TF300T:
1. Place the downloaded rooting package file on the Desktop of your PC.
2. Connect your tablet to your PC using the USB cable.
3. Transfer the Rooting Package ZIP file to your tablet’s internal storage.
4. After the file is transferred successfully, disconnect the tablet from the PC.
5. Turn OFF your tablet.
6. Boot your tablet into the recovery mode. Press and hold Volume DOWN+Power keys together and a message will popup on the screen saying “Press Vol. UP to enter RCK (5s).”
7. Press the Volume UP key and you will be in the CWM recovery mode.
8. From the main menu of the recovery, choose install zip from sdcard option followed by choose zip from sdcard.
9. Navigate to the ZIP file you transferred earlier to your tablet and select it using the Power key. It will begin flashing the file.
10. Once the flashing is done, get back to the main menu and choose reboot system now.
Well done, you successfully rooted your Asus Transformer TF300T tablet and now you can install the Root-only apps on this device.
If this procedure helped you in rooting your tablet, then please head over to the official thread over at XDA Forum to thank/donate to the original developer of this root method !