For years, the researchers have been interested in studying the deterioration caused by microorganisms in the cinematographic heritage. To study the biodeterioration caused by microorganisms not only techniques of identification of microorganisms are used but also the microscopic techniques to observe of their structures and the damages in the materials. In Cuba, electron and epifluorescence microscopy are applied in multiple branches of scientific research but so far it is unknown to use it to study the affectation that may have the biodeteriorated documentary supports in our heritage institutions. Therefore the aim of the present work is to apply different microscopic techniques to study the biodeterioration caused by microorganisms in cinematographic films of patrimonial value. Optical microscopy, environmental scanning electron microscopy (ESEM), vacuum scanning electron microscopy (SEM) and epifluorescence microscopy (EPI) were used. An important microbial colonization, fundamentally fungal on both sides of the films was evidenced with the ESEM and SEM. In addition, a dense biofilm and a bio-fouling formed mainly by mites and pollens were observed. The presence of small holes in the fungal structures as a result of the lytic activity of  the bacteria was observed. For the other hand, fluorescence microscopy showed that the majority of the microorganisms on the films were still viable and active. For the first time in Cuba, the microscopic techniques were used to evidence the presence of viable and active microorganisms. Those microorganisms are responsible of the biodeterioration in cinematographic films of heritage value.