The Midou(French pronunciation: [midu]; Occitan: Midor) or Midour is the left precursor of the Midouze, in the Southwest of France.

The Midou rises in Armagnac, in the Gers département. It joins the Douze in Mont-de-Marsan to constitute the Midouze, a tributary of the Adour. It is considered the upper course of the Midouze by Sandre.

• Gers: by Nogaro
• Landes: Villeneuve-de-Marsan, Mont-de-Marsan

• (R) Riberette or Midour de Devant.
• (R) Midouzon,
• (L) Izaute, from Termes-d'Armagnac,
  • (R) Jurane,
• (R) Estang.
• (L) Ludon, from Le Houga.

N.B. : (R) = right tributary; (L) = left tributary