My Macbook Pro shuts down after turn it on.

Try these steps:

Restart your Mac with the Shift button pressed.

- Shut down your Mac

- Wait until your computer turns off and after that press the Power button

- Right after you hear the startup tone, press and hold the Shift key

- Release the Shift key when you see a grey Apple sign and the progress bar below this sign

- Once you see Desktop, start a Disk Utility scan to detect and repair file system errors (don't forget to choose your main hard drive)

- Click on Verify Disc and then, if asked to fix problems, on Repair Disk

- After this, click on Verify Disk Permissions and then on Repair Disk Permissions

- After the process is finished, shut down your Mac and turn it back on after about 30 seconds

Apart from that, take a look at this Apple article and follow the instructions on Resetting NVRAM shown there:How to Reset NVRAM on your Mac - Apple Support

Try these steps: Resetting the System Management Controller (SMC) on your Mac - Apple Support

Take a look at the steps suggested by Apple in this article:

https://support.apple.com/en-us/HT204267

Hope this helps!

Try all the steps.

It would be helpful if you indicated the EXACT model MBP that you have and the current OSX.

Ciao.

Use the original Snow Leopard installation disk and boot the MBP as if you were reinstalling the OSX.

After the language selection, the next display should show a menu bar on top.

Select UTILITIES.

From the drop down menu, select Disk Utility.

Run Disk Utility>First Aid, Verify and Repair.

If the disk cannot be repaired. it will have to be replaced.

Ciao.

Your best option is an appointment at an Apple store genius bar for a FREE evaluation.

Ciao.

Based on what you have tried, I have doubts that you will be able to repair the MBP yourself. Consider shipping the MBP to Apple for evaluation and repairs.

Ciao.