The ichthyological collections of NMNHS contain more than 13000 specimens of recent fish from Bulgaria and other countries. There are materials mainly from Europe, but also from Central Asia, Vietnam, Mexico, etc.
The collection was established more than 120 years ago and contains historical materials collected for the museum from well known zoologists like Pencho Drensky, Kiril Bulgurkov, Georgi Shishkov and others. Former curators of the collections were Pencho Drensky and Lilyana Muhajlova.
The exposition hall and depository were fully renovated in 2009 and 2013 respectively.