He was a member of Shinkō Shashin Kenkyukai (新興写真研究会, , New Photography Research Society) which was founded by Sen'ichi Kimura (木村専一) in 1930.
In 1932, Horino published a monograph Camera, Eye x Iron, Construction (カメラ・眼×鉄・構成) which is one of the most important works for Japanese modern photography (Shinkō Shashin, 新興写真).
This monograph consists of photographs of ships and architectures made of steel, such as bridges, tanks and towers, based on his own sense of beauty, "a beauty of machinery" (機械美学), derived directly from the theories of the art critic (photo critic) Takaho Itagaki (板垣鷹穂), using, for example, close-up and looking-up.
1931, editing and design by Takaho Itagaki, Chūōkōron October issue) and Flowing through the City - Sumida River Album (Shutokanryū - Sumida-gawa no Arubamu, 首都貫流-墨田川のアルバム, 1931, editing and design by Tomoyoshi Murayama, Hanzai Kagaku December issue).
The photos produced by Masao Horino contributed to the world wide cry for the bombs to never be used again.