Objective:To investigate the correlation between -415T/C and -462G/A single nucleotide polymorphism in the promoter region of chromogranin A(CHGA) and prognosis of critically ill patients. Methods:Totally 294 critically ill patients consecutively ad-mitted to our ICU were recruited. The -415T/C and -462G/A genetic polymorphisms of CHGA were determined the by polymerase chain reaction and DNA sequencing technology,and correlation between genotype and clinical characteristics of patients were ana-lyzed. Results:①There was no significant difference in the minor allele frequency(MAF) of CHGA-415T/C and CHGA-462G/A ge-netic polymorphism between participants of this study and the healthy people in Asia.②The CHGA-415T/C MAF of death group was significantly higher than that of survival group(MAF 0.378 and 0.292 respectively,P=0.046),but there was no significant difference in the CHGA-462G/A genetic polymorphisms between the two groups(MAF 0.096 and 0.107 respectively,P=0.717). ③ Survival analysis showed that there were significant differences between CHGA-415T/C mutation group(including TC and CC genotypes) and wild group(TT genotype)(Log rank=7.331;P=0.007). The mortality in mutant group was significantly higher than that in wild group(0.325 and 0.191,respectively;P=0.010). Binary logistic analysis showed that CHGA-415T/C polymorphism was an independent risk factor for the mortality of critically ill patients(OR=2.055,95%CI=1.051-4.019,P=0.035). Conclusion:Critically ill patients with CHGA -415T/C mutant genotype display higher 30 d mortality than wild genotype group. Furthermore the death group had higher MAF than survival group. The CHGA -415T/C polymorphism could be an independent risk factor for 30 d mortality in critically ill patients.