This work describes a new preparation method of carbon-xerogel films with well-developed mesoporosity from resorcinol - formaldehyde polymerization. The particular effect that the microwaves have during the assisted carbonization process shows that with low microwave carbonization degrees, high mesopore volumes can be obtained. Carbonization assisted by microwaves yields carbon-xerogels films whose aromatic and chemical characteristics are clearly different than those obtained by conventional thermal carbonization with similar carbonization degrees.