The two words are similar and, in some contexts, are interchangeable. However, relief is usually "relief from anxiety or suffering" while "release" is "release from being bound, captured, arrested or imprisoned". I was relieved to find out that you were not injured in that terrible car accident. Antacids can give you relief from acid indigestion. Prisoners are released when they have served their sentence. Doves are sometimes released at weddings. Relief also has other specialized meanings. If a city is under siege, the inhabitants hope that friendly forces will come to relieve them. Also, if a soldier is assigned to a post (e.g. guard duty), when his watch is over, the next soldier relieves him. Or, if an officer has been relieved of command, that means he has lost his job as the commanding officer of a military unit and someone else will relieve him (i.e. take over his job). Finally, when someone is suffering from a long and difficult illness, death is often referred to as a "release" from the suffering that he has been going through. Are you relieved that this explanation is finally done? I will now release you from having to read any more of this tonight.

release : when something treppen and u set him free relief : when you have problem and it was solved.then u r relief

The word RELIEF defines in many context such as forms of help and probably an immediate solutions or cure while the word RELEASE means to set free or to open up as well to let it go..make sense?

the first is a noun, the second a verb