A crystalline oxide semiconductor film with an enhanced electrical property is provided. By use of a mist CVD apparatus, a crystalline oxide semiconductor film with a corundum structure and a principal plane that is an a-plane or an m-plane was obtained on a crystalline substrate by atomizing a raw-material solution containing a dopant that is an n-type dopant to obtain atomized droplets, carrying the atomized droplets by carrier gas onto the crystalline substrate that is an a-plane corundum-structured crystalline substrate or an m-plane corundum-structured crystalline substrate placed in a film-formation chamber, and the atomized droplets were thermally reacted to form the crystalline oxide semiconductor film on the crystalline substrate.