The global economy seems to be sinking in the ocean of plastic wastes. Plastic circular economy has been prescribed the key panacea with recycling as its key strategy. The issue of sustainable plastic circular economy has so far been the challenge amid the production of virgin plastics. The aim of this study is to assess the sustainability of plastic circular economy with complete dependence on plastic wastes. Sustainability assessment criterion was based on plastic waste generation and recycling transitional probabilities. A closed system is assumed to ensure that no new virgin plastic is produced. Data was obtained from various publications of the Plastic Europe; and other research publications on plastic waste management. Sustainability was then assessed under four scenarios; joint force of plastic waste incineration and discarding, plastic waste discarding without incineration, plastic waste incineration without discarding; and complete riddance of plastic waste incineration and discarding. It was revealed that the already cumulated volume of global annual plastic waste generated can sustain plastic circular economy in a closed system only if plastic waste incineration and discarding are completely prohibited. The study is an indispensable tool for policy formulation in the area of waste management.