This book mainly discusses the degree factors and the component factors in graphs， and is divided into five chapters. In c.hapter 1， we give the basic terminologies， definitions， graphic parameters， background and significance of the study. In chapter 2， we discuss the existence of fractional factors with given properties in graphs. In chapter 3，we present some definitions related to all fractional factors of graphs and derive some results for graphs to admit all fractional factors.In chapter 4， we study orthogonal factorizations in graphs or digraphs which are natural improvements and generalizations of the previous results. In chapter 5，we study component factors of graphs and gain some interesting results on the existence of component factors in graphs.
　　This book is a useful reference for college students and graduate students.

Chapter 1 Introduction
1．1 Definitions and Terminologies
1．2 Graphic Parameters
1．3 Background and Significance of the Study

Chapter 2 Fractional Factors in Graphs
2．1 Degree Conditions and Fractional K-Covered Graphs
2．2 Fractional Factors with Given Properties in Graphs
2．3 Fractional（g，f，n，）-Critical Graphs
2．4 Fractional ID-[a，b] -Factor-Critical Graphs

Chapter 3 All Fractional Factors in Graphs
3．1 All Fractional Factors with Inclusion Properties
3．2 All Fractional Factors with Exclusion Properties
3．3 All Fractional ID-[a，b] -Factor-Critical Graphs

Chapter 4 Orthogonal Factorizations of Graphs
4．1 Orthogonal Factorizations in Bipartite Graphs
4．2 Orthogonal Factorizations in Digraphs

Chapter 5 Component Factors in Graphs
5．1 A Characterization for Star-factors of Graphs
5．2 Path-factor Covered Graphs
5．3 Path-factor Deleted Graphs
5．4 Path-factor Critical Graphs

References