Synthetic resins have been extensively employed by artists in their works of art, e.g. as paint binders, or by conservators for conservation treatments, e.g. as stone consolidants and protectives. It is generally thought that synthetic resins are less prone to chemical, physical and biological deterioration than other organic products but there are many articles in the scientific literature and some reports in the conservation of cultural heritage literature claiming that microorganisms are capable of degrading synthetic resins. This paper reviews the researches on the biodeterioration of synthetic resins used in the conservation of cultural heritage, including stone, painting and textile materials, carried out in the last fifty years.