is there a consequence of using death note?

Yup there is. One is that the person that uses the death note will not go to heaven or hell.

The immediate effects are that you can't go to heaven or hell, just 'Mu'. It's hypothesized that this actually means you become a Death God, since Shinigami's live in neither heaven or hell, and in the Relights there is a Shinigami who might be Light, but we aren't sure.
Other than that, there is the complete and untter shattering of conscience, morals, and sanity. If you keep killing, you'll lose your conscience, morals and sanity. If you don't, most likely you'd simply destroy or disown it, but still... some piece of your sanity would be gone whether you lost the memories of the Death Note or not. Absolute power corrupts absolutely.

With using the death note, there are of course consequences, like most things in life. Some of the consequences are that the human or any human that shall use the death note can either go to heaven or hell, the person in possession of the DEATH NOTE, is possessed por a God of Death, until they die, and lastly the owner of the DEATH NOTE can in exchange for half of his/her life, can get the eyeballs of a Death God, which enables them to see a human name and their remaining lifeline when looking through them...

Yrs, YOu can not go to heaven or hell just "mu" One of the most poular theries is that you become a shinigami. You also end up losing your life to the shinigami.