Bioenergy is now accepted as having the potential to provide the major part of the projected renewable energy provisions of the future. It has been ascertained that the biomass is a common form of renewable energy and widely used in the world. The use of biomass to provide energy has been identified as a fundamental to the development of civilization. There are different types of thermo-chemical conversion technologies available for converting biomass into energy which stretches from direct burning to more complex processes including gasification or pyrolysis. Among these processes, pyrolysis has become increasingly popular because it gives products of better quality compared to any other thermo-chemical conversion processes for biomass. A computational fluid dynamics (CFD) model is developed using Advanced System for Process Engineering (ASPEN) PLUS which is a computer assisted energy simulation tool to analyse and optimize the performance of pyrolysis process i.e., to maximize the yields of pyrolysis products such as bio-oil, biochar and syngas as a function of pyrolysis temperature, operating conditions, and physical and chemical properties of biomass. The simulation was done for four types of biomass, namely shredded green waste, pine chips, wood and birch. The results show that the shredded green waste is the best for bio-oil production which possesses high cellulose and low moisture content. The bio-oil of up to 58% can be produced from this material.