Plant-based biomass resources, including cereals, crop residues, seed of oil crops, sugar crops, forage crops and various woody crops, can be converted to several of bio-products through physical, chemical and biological conversion methods. Although the components of different plant-based raw materials are varied, there are four main compounds: carbohydrate (sugar, starch, cellulose and hemicellulose), lignin (poly-phenol), esters and protein. This new and important book aims to analyse the common problems of the conversion process of plant-based products starting with the key problems of the complexity of the plant-based raw materials, the 'process integration' of process engineering, and the 'structure and function' of product engineering. The concept of 'plant-based products process engineering' is advanced based on the integration of multidisciplinary knowledge, and the system of multilevel conversion is expatiated from the three areas: raw materials, conversion process and product development. These afford a theoretic and technologic support for development of plant-based products process engineering. This book also introduces the key technology platforms for plant-based products process engineering, the main approaches for using these platforms to achieve a multi-level utilisation of plant-based raw materials, and the constitution of a novel mode for the ecological industry of plant-based products.