Excision repair cross-complementing 1-118 single nucleotide polymorphisms (SNPs) have been reported as predictive markers of response to platinum-based chemotherapy. Currently, the most used methods for genotyping of SNPs are costly and time consuming. It is necessary to develop a method that is more accurate, cost-effective, and simple. An improved fluorescence polarization assay based on asymmetric polymerase chain reaction hybridization for screening excision repair cross-complementing 1-118 SNPs has been developed. Excision repair cross-complementing 1-118 SNPs of all 907 samples were analyzed in sequence and improved fluorescence polarization assay in parallel. The sensitivity, specificity, and stability of the improved fluorescence polarization assay were measured. This study showed the accuracy, simplicity, and cost-effectiveness of the fluorescence polarization assay in the detection of excision repair cross-complementing 1-118 SNPs in a panel of 907 samples. The fluorescence polarization assay was more accurate for the heterozygous sample than was the sequence assay. The minimum detection level established with the fluorescence polarization assay was 2.5 genome copies per reaction and no cross-reaction was observed.