Truls Johannessen Wiel Graff (16 April 1851 – 1918) was a Norwegian county governor.
He was the youngest living son of captain Christian Fredrik Graff (1818–1893) and Cathrine Magdalene Bull Wiel. In 1882 he married Benta Tomine Marie Cathrine Baastad.[1] Their son Ragnvald Graff became a major and barrister.[2]
In 1890 he was the acting County Governor of Hedmark, and from 1896 to 1906 he served as the County Governor of Finnmark.[3]