Palazzo Mansi, site of the National Pinocoteca since 1977, is one of the richest lordly residences in Lucca. The main core of the building was constructed in the 16th and 17th centuries, encapsulating more ancient buildings; work on the decoration scheme was completed in the 18th century. Dating from the 19th century are the two wings at right angles to the central core. The monumental staircase is striking, consisting of a single ramp of stairs leading to the piano nobile in a loggia overlooking the garden.

The main core of the Museum consists of the monumental apartment on the piano nobile, where the paintings from the collection donated by Grand Duke Leopold II of Lorraine and those surviving from the Mansi collection are displayed. The ground floor is used for temporary exhibitions, while paintings by nineteenth-century artists from Lucca are exhibited on the second floor.

The institution also holds interest from the scientific point of view. On the second floor is a section illustrating the important role played by Lucca in the production of precious fabrics. The collection includes a number of pieces dating from the 16th century to the end of the 18th, among them some seventeenth-century liturgical vestments in damask, the most important fabric from the local production. There is also a sample collection of about 80 pieces, interesting for studying production from the 16th through the 19th century. Lastly, the collection of the Tongiorgi Legacy, including Coptic fabrics from the 6th through the 10th century, is of the priceless value. The section has a laboratory of weaving craftsmanship.

The Pinacoteca also has, on loan from the Museo Nazionale di Villa Guinigi, the Hospital of San Luca Collection, formed of objects coming from the Hospital itself and from churches in the Province of Lucca, dating from the 18th and 19th centuries. They include, among other things, of a collection of weights, measuring instruments, scales and pharmacy jars.