Jacket having a warming pocket in which pockets on both sides can be joined and separated

Disclosed is a jacket having warm pockets with both pockets being attachable and detachable which is characterized in that in an ordinary jacket which can be opened and closed by a certain engaging element such as a zipper and buttons and has a pocket at left and right sides formed about the engaging element, respectively, for a user to insert his hands into the left and right pockets, both the separated pockets can communicate like one longitudinal pocket, and a tube-like passage is formed from both the pockets and the backside of a jacket, and a warming element is accommodated in both the pockets or the tube-like passage for the purpose of effectively warming the hands of a user as well as a user's body.