Ingvald Johan Suphammer was a Norwegian architect.
Suphammer was educated in Germany and later at the School of Arts and Crafts. He initially worked as a carpenter before becoming an architect. He ran an architectural firm together with his son, Kaare Olav Suphammer.
Suphammer designed numerous residential buildings in Oslo, following the architectural trends from Art Nouveau through Neoclassicism to Functionalism. Among the buildings he designed was Løvenskiolds gate 11, where he lived from its construction until his death.
Additionally, he designed assembly halls (e.g., for the Salvation Army) and conducted surveys of stave churches. Apart from his work in Oslo, he also undertook projects in Hamar and Odda. Suphammer was a co-founder of the Lodge Fridtjof Nansen of the Odd Fellows order, and he designed the lodge's seal.
Suphammer is interred at Vestre krematorium (crematorium) in Oslo.