Plastic is a packaging material used as a container to protect and store food as well as non-food products essential for the community, specifically in Indonesia. This study aims to examine the effect of glycerol addition as a plasticizer on the physical characteristics of biodegradable plastic made from oil palm empty fruit bunches (OPEFBs). It was conducted through an experiment using a completely randomized design (CRD) consisting of 5 treatments and three replications. The treatments include P1, P2, P3, P4, and P5 with 1%, 1.5%, 2%, 2.5%, and 3% glycerol, respectively, in the formulation of biodegradable plastic. The results showed that the addition of glycerol had significant effects on water resistance, vapor transmission rate, tensile strength, and elongation, but had no significant effect on the biodegradability of plastic. Furthermore, the addition of glycerol as a plasticizer improved the elongation of biodegradable plastic made from OPEFB, but did not improve the characteristics of water resistance, vapor transmission rate, and tensile strength. The P1 treatment produced the best result as it generated a water resistance of 2.226%, vapor transmission rate of 16.306 g/m2/hour, tensile strength of 2.430 MPa, and elongation of 18.950%. In addition, the biodegradable plastic was able to decompose in two weeks.