Did you press the battery charge button to see the battery charge level?
Look at this support article:
It may be helpful if you provided detailed information on your MBP, such as year, model, OS.
http://support.apple.com/kb/TS1365 Intel-Based Apple Portables: Troubleshooting a computer that will not power on
If you are still under warranty and/or have AppleCare, call them. Let them deal w/it. Out of warranty, time to take a trip on down to your local Apple Store or an AASP if the above Article does not work.
Yes if your model MBP has a removable battery. If it does not:
- Shut down the computer.
- Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
- On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
- Release all the keys and the power button at the same time.
- Press the power button to turn on the computer.
Note: The LED on the MagSafe power adapter may change states or temporarily turn off when you reset the SMC.