Holum is a former municipality in Vest-Agder county in Norway. It is located in the northern part of the present-day municipality of Mandal.
The municipality (originally the parish) was named after the old Holme farm (Old Norse: Holeimr), since that is the location of the church. The name is a combination of the word hol or hull meaning "hole" and the word heimr meaning "home". The spelling of the name was changed from Holme to Holum in 1911.
The parish of Holme was established as a municipality on 1 January 1838 (see formannskapsdistrikt). On 1 January 1964, most of Holum (population: 1,127) was merged with the town of Mandal and the municipality of Halse og Harkmark to form an enlarged Mandal municipality. The remainder of Holum (the Stubstad and Svalemyren areas, with a population of 9) were merged into the neighboring municipality of Søgne.