Starch is the main physiochemical basis for rice grain quality, and fine tuning of the starch content/composition is an important target in rice quality breeding. This study attempts to uncover specific rice germplasms that contain different starch content and determine their genotypes, in order to provide useful information for understanding the regulation network of rice starch synthesis as well as quality rice breeding. 119 rice accessions, which were collected from National Observatory of Rice Germplasm (Nanjing, Jiangsu), were examined for the amylose content using an improved method without boiling water bath. The Wx genotypes with extremely high and low amylose content were genotyped by a dCAPS marker. Out of the resistant starch content of 15 accessions with high amylose content, three were genotyped for SSIIIa and SBEIIb if compared to Nipponbare. The results showed that the updated method showed an accuracy similar to the current national standard, but became simpler and easier in the operation procedure. Most of accessions showed 9.0%-33.0% on the amylose content, and 1.0%-4.5% on resistant starch content. The genotyping using dCAPS marker showed the Wxa allele generally in the Wx genotypes of high amylose accessions. Compared with Nipponbare, three accessions (including Lixinjing, Nantehao and Chenwan3) with high resistant starch contained three common mutations in SSIIIa, among which the 2362th nucleotide in the third exon resulted in a missense mutation. Likewise, a common missense mutation in the 96th nucleotide in the fourth exon of SBEIIb gene was detected in two high resistant starch accessions (Lixinjing and Nantehao). These missense mutations might be responsible for the increase of resistant starch content in rice, providing insights for precisely editing of key genes and creating new germplasms associated with starch quality traits.