The Numismatic Room was established in 1883. The initially modest collection expanded mainly thanks to the generosity of private benefactors such as Henryk Bukowski. The 1903 donation of Emeryk Hutten-Czapski's collection resulted in a radical change in the rank of the Room, which became the repository of the most representative collection of Polish coins, medals and banknotes, featuring a number of unique objects (e.g. Bolesław Chrobry's GNEZDVN CIVITAS denarius or Władysław Łokietek's ducat).

More donations soon poured in, including coin hoards (Dzierznica, Pełczyska). Objects were also acquired though purchases and exchanging duplicates. After World War II, the Room was enriched with further endowments, including antique coins from Karol Halama, the Piast dynasty coins from Jadwiga and Andrzej Kleczkowski (Zygmunt Zakrzewski's bequest) and - in recent years – antique and fake coins from Lech Kokociński as well as donations from William Stancomb, Jacek Budyn, Tadeusz Zawadzki, Mirosław Kruszyński and Jan J. Kołecki. The collection is continuously expanded with further purchases.

Currently, the Room boasts a collection of approximately 109,000 objects. It comprises items such as antique coins (c. 9000 objects), Polish and foreign coins (c. 60 000), medals (c. 7000), religious medallions (2646), banknotes (c. 19 000), varia (c. 6200) and deposits (c. 4400).

Particularly noteworthy antique objects include Alexandrian, Celtic and Greek coins from the archaic period, while coins dating back to the Roman Empire are the most numerous.