The presence of greenery in the space of historic markets was conditioned depending on the historical era: function, aesthetics or ecological needs of the city. The purpose of the work is to show the contemporary functions of greenery in the space of historic markets in the context of conditions for sustainable development (ecological, social, economic and ethical) and their relationship to the latest conservation doctrines (document from Nara—1994, Cracow Card—2000, orthodox creation). The paper analyzed 52 cases of town and city markets in the Podlaskie Voivodeship (Poland), which allowed conclusions to be drawn regarding the treatment of greenery in public spaces of markets. The results of the work may be helpful in the process of designing and modernizing the markets in the Podlaskie Voivodeship and in Poland, and more widely used for further research on the use of greenery in public space and assessing the effects of its presence.