"After careful thought and much consideration, Sean has made the difficult decision to call the wedding off," Big Sean's rep said in a statement.
The two became engaged last October after dating publicly since April 2013.
The rapper also denied media reports that he had cheated on Rivera.
"The recent rumors and accusations reported by so-called or fake sources are simply untrue. Sean wishes Naya nothing but the best and it is still his hope that they can continue to work through their issues privately. We will not be commenting again on this matter."