According to divorce documents, Wonder and his wife of 11 years have been separated since 2009. Citing irreconcilable differences, Wonder is seeking joint custody of the couple's two sons, Kailand, 10, and Mandla, 7.
The financial details of the proposed divorce have not been disclosed, but Wonder has agreed to pay both spousal and child support to Morris.
Wonder, whose legal name is Stevland Morris, signed the document with two fingerprints.
The "Isn't She Lovely" icon's first marriage, to singer Syreeta Wright, lasted from 1970-1972. He wed Morris, a fashion designer, in 2001. He has seven children from various relationships.