The station opened on 20 January 1902 at the same time as the Trunk Line received double track.

The Trunk Line was moved around the terminal and Alna Station opened on it to serve commuter trains.

[3] The Norwegian Trunk Railway bought a 2.6 hectares (6.4 acres) plot of land at Alna in October 1897, with the plans of building a classification yard and station there.

[4] In June 1899 it signed an agreement with the Ministry of Labour that the Trunk Line from Christiania to Lillestrøm would receive double track.

Traffic had increased significantly along the line as so the Norwegian Trunk Railway commissioned new station buildings most places.

[5] Alnabru was thus built in the same style, with Finn Ivar Andreas Knudsen as architect.

[7] The Norwegian State Railways bought the farm Nordre Alna in 1918, allowing for a further development of the station and cargo areas.

[10] This forced the Trunk Line to be rerouted past the freight yard, resulting in a new 1.1-kilometer (0.68 mi) section of track being built on the north side.