In 1920, Gdynia began to grow very quickly as a city and a port under the Second Polish Republic, and this resulted in a significant increase in passenger rail traffic.

Therefore, between 1923 and 1926, a new imposing art-deco (with regional Pomeranian accents) main building was constructed, designed by Romuald Miller and opening on 15 July 1926.

Its interior featured a large waiting room, ticket windows, toilets, luggage storage, a restaurant, bookstore, money exchange, and hairdresser.

In the station's main waiting room several notable wall and ceiling frescoes of sea landscapes were re-discovered during the 2008 renovation after having been covered over in the intervening years.

In the dining hall, the wall paintings depict the celestial bodies and signs of the zodiac, and a mosaic illustrates Pegasus.