The estimation of environmental degradability of different ramie fibre reinforced biocomposites in Baltic Sea water and in compost with activated sludge under natural conditions is the subject of this paper. The characteristic parameters of environments were monitored during incubation time and their influence on the rate of degradation of biocomposites was discussed. The degradation processes of two kinds of biocomposites, ramie fibre/Ecoflex® and ramie fibre/cellulose nanofibre reinforced corn starch resin, were studied by macro- and microscopic observations of polymer surfaces, changes of weight, and tensile strength during incubation under natural conditions. The macro and microscopic observations and weight changes confirmed the decrease of the tensile strength both of the composites after incubation in compost and in sea water. It was demonstrated that the biocomposites with natural fibre of ramie were degraded in compost faster than in sea water, due to different microbial communities. The ramie/Ecoflex® biocomposite was degraded more distinctly than ramie/cellulose nanofibre reinforced corn starch resin biocomposite in both natural environments.