The 1999 Grand Prix Hassan II was an Association of Tennis Professionals tennis tournament held in Casablanca, Morocco.

It was the 15th edition of the Grand Prix Hassan II and was held from March 22 to March 29, 1999.

Alberto Martín defeated Fernando Vicente, 6–3, 6–4.

Fernando Meligeni / Jaime Oncins defeated Massimo Ardinghi / Vincenzo Santopadre, 6–2, 6–3.