Rice is one of the most important crops worldwide. In recent years, with the improvement of life quality, people have paid more attention toon the taste of rice. Endosperm is the main component of rice grain, which provides energy for seed germination and embryo development. Starch accounts for ca. 80% in rice grain. Unlocking the molecular mechanism of starch synthesis becomes of theoretical significance and application value in improving rice quality. Although the general pathway of starch synthesis has been relatively illustrated, this process is still complicated considering the genetic and environmental interaction under field conditions. Due to the difficulty of phenotypic identification, it is difficult to genetically map and isolate the genes/QTL that affect rice quality. Mutants defected in starch synthesis via physical and chemical mutagenesis were mostly controlled by single nuclear gene, enabling the isolation of the number of new genes found in the past years, and uncovering the divergent pathways involved in starch synthesis. This paper summarizes these starch synthesis related mutants isolated in recent years, and discusses different metabolic pathways involving in starch synthesis, which expects to provide reference for rice breeding and quality improvement.