The Botanical Museum, established in 2007, is a structure of the Department of Life Sciences of the University of Siena and includes the two historical university museums / laboratories: the Botanical Garden and the Herbarium.

The Botanical Garden of Siena has been located since 1856 within the ancient city walls, in the valley (about 2.5 hectares) that opens between Porta Tufi and Porta San Marco. It preserves over 2,000 plant species, from the typical Mediterranean ones of the Tuscan environment to the most original ones from exotic countries. The structure visible today, organized in the style of Italian nineteenth-century gardens, is an evocative place, with numerous testimonies that trace its history back to the sixteenth century. The remaining large portion of the garden that opens into the valley, however, retains the appearance of a farm, interspersed with rocky and humid areas for the presentation of particular Tuscan environments.

The Herbarium (Herbarium Universitatis Senensis) is located in two air-conditioned rooms of the Department and constitutes a precious source of botanical and historical information, as well as an indispensable research and teaching tool for the University. The Herbarium consists of over 90,000 dried vascular plants, lichens, bryophytes, fungi, algae and is divided into different sections: the Historical Collections and the Collections.