Giovanni Valentino Mattia Fabbroni (13 February 1752 – 17 December 1822) was an Italian naturalist, economist, agronomist and chemist.

Giovanni Valentino Mattia Fabbroni was born in Florence, Italy, the son of Horace and Rosalinda Werner.

From 1777 to 1778 he wrote Reflexions sur l'état actuel de l'agricolture, a work which had a considerable impact on farming in Tuscany.

Fabbroni took on an increasing role in Florentine society as a proponent of economic liberalism and agrarian reform, and was a supporter of Leopold II.

[2] This last consists of the many letters and notes concerning the Royal Museum of Physics and Natural History of Florence, which offer access to the various activities of study and research promoted by the institute, as well as its management.