This paper presents results of dendrochronological analysis of spruce wood from the Wieliczka Salt Mine, one of the oldest mines in Poland. The wood came from the first level of the mine, from casings of drifts, chambers, mineshafts, short shafts, galleries and chapels. The oldest wood, representing spruce trees cut down in the 15th century, appears in the Wałczyn, August and Dusząca chambers, Bąkle chamber and Powroźnik gallery, as well as the cast between the Kaczorowski and Sroki chambers. Younger wood, from the 16th and 17th century, was recognized in the Krupiński, Dusząca, Reyna and Weszki chambers, the Leszno and Karol galleries, the Sułów short shaft, and the Lizak chapel. The 18th–19th century wood appears in the August, Wałczyn, Dusząca, Rex and Kloski chambers, the Klemens gallery, the Piżmowa chapel, and the Wałczyn short shaft. In two excavations of the August and Weszki chambers, fragments of 20 th century wood were recognized. Wood from old mines is a valuable source of information on history of the mining excavations or tools used in the mines. It also allows extending the scope of research of the mining archaeology.