Maad a Sinig Maysa Wali Jaxateh Manneh (Serer proper : Maysa Waali Maane, many variations : Maysa Waaly Dione, Maïssa Wali Dione, Maysa Wali Jon, Maissa Waly Mané, etc.) was a king described in the oral tradition of the Serer pre-colonial Kingdom of Sine and the first of the Guelowar maternal dynasty to rule in Serer country. He reigned as Maad a Sinig (king of Sine) from c. 1350 to 1370.