It's Saint Laurent

SHINee's Key posted up a photo on instagram yesterday wearing not one, but two pieces from the brand's Ready to Wear line.

He wore the Saint Laurent Multi Zip Motorcycle Jacket in Black Leather as well as the Long sleeve Mariniere Shirt in Navy Blue and Natural (or possibly the short sleeved version available here).
BIGBANG leader GD wore the black and ivory version of the jacket at 2NE1's world tour afterparty.
Lyn
Do not take without proper credit, thanks!
Image Credits:  bumkeyk, saint laurent
Also See: Request: Onew's Sweater Jonghyun's Blue Night with Taeyeon Airport fashion: SHINee