The 1951–52 Landsdelsserien was a Norwegian second-tier football league season, the first named Landsdelsserien. The league was contested by 54 teams, divided into a total of seven groups from four districts; Østland/Søndre, Østland/Nordre, Sørland/Vestland and Møre/Trøndelag. The two group winners in the Østland districts, Larvik Turn and Lillestrøm promoted directly to the 1952–53 Hovedserien. The other five group winners qualified for promotion play-offs to compete for two spots in the following season's top flight. Varegg and Ranheim won the play-offs and were promoted.