Herman Isaachsen Willoch (27 June 1892 – 11 February 1968) was a Norwegian painter.
He was born in Alversund[1][2] as the son of vicar Christian Abel Isaachsen, a grandson of Isaach Isaachsen. He was the cousin of Odd Isaachsen Willoch.[3] The family eventually moved to Uranienborg, Oslo.[2] He later resided in Bærum.[4]
He studied under Pola Gauguin at the Norwegian National Academy of Fine Arts. He worked mainly with frescoes, decorating the city hall in Sandvika.[1]
He is buried at Vestre gravlund.[5]