On August 1, 1927, the uyezds were abolished and Oranienbaumsky District, with the administrative center in the town of Oranienbaum, was established. The governorates were also abolished, and the district was a part of Leningrad Okrug of Leningrad Oblast. Bolshaya Izhora was a part of the district. On July 23, 1930, the okrugs were abolished as well, and the districts were directly subordinated to the oblast. On August 27, 1939 Bolshaya Izhora was made an urban-type settlement. Between August 1941 and January 1944 the eastern part of the district, including Bolshaya Izhora, served as a territory, known as Oranienbaum Bridgehead, which protected the city of Leningrad form German troops. On February 23, 1948 the town of Oranienbaum was renamed Lomonosov to commemorate Mikhail Lomonosov, and the district was renamed Lomonosovsky.