Glass fibers are the most widely applied reinforcing fibers in polymeric composites and provide stiffness, strength as well as thermal and chemical resistance. Such glass fibers are available with suitable sizings to be chemically compatible to the selected polymer matrix. In light of the increasing use of biobased polymers, the challenging point of composite recycling is addressed in this work. A new approach for the development of biodegradable glass fiber reinforced composites is presented, based on both a degradable matrix and hydrolytically active glass fibers that also includes the use of biobased and degradable sizings. In our work, we successfully treated degradable glass fibers with silanes and biocompatible film formers with the aim to enhance the fibers' tensile strength, but also to show the effect of the sizing process on the fibers' degradation. The biobased sizings increased the single fiber tensile strength, however, the film formation on the surface needs to be further improved.