Peter Malberg (Aarhus, 1887 – Glostrup, 1965) was a Danish stage and film actor, best known for playing an uncle in the comedies of the Far til fire series. He trained as a painter, but his career moved towards the stage and the screen.
In 1904 he began an apprenticeship as a painter with C. Christian Nielsen and soon after the Aarhus Theatre hired him to paint sets. Watching the acting of his older brother, the actor Henrik Malberg, led him to perform himself. He made his debut in 1907 at the Aarhus Theatre in Ranke viljer. After touring Norway, Sweden and Finland, from 1913 he worked in theatres in Copenhagen. His most successful stage role was Balder Svanemose in the comedy Peter den Store (1930), which he performed more than a thousand times.
Between 1910 and 1913 he appeared in 22 silent films, including David Copperfield (1922). His most prominent film work was the Far til fire series, and he also acted in nine films by Morten Korch. He remains associated with mid-twentieth-century Danish family comedy. He had been married since 1925 to the actress Ellen Nimb-Olsen.