Background Evaluating cirrhotic severity is essential for individualizing surgical modalities for patients with hepatocellular carcinoma (HCC). Our previous study proposed a non-invasive method named cirrhotic severity scoring (CSS) to stage liver cirrhosis. Indocyanine green retention rate at 15 min (ICG-R15) has been widely used for the preoperative evaluation of hepatic functional reserve; however, whether ICG-R15 is well correlated with cirrhotic severity, and especially whether comparable with CSS in predicting cirrhotic severity in HCC patients with Child-Pugh grade A liver function remains unknown. Methods Overall, 510 HCC patients with Child-Pugh grade A liver function undergoing hepatectomy between January 2011 and December 2014 were retrospectively studied. Cirrhotic severity was pathologically assessed using the Laennec staging system. The correlations between ICG-R15, CSS, and cirrhotic severity were analyzed. Furthermore, the performance of ICG-R15 and CSS in predicting posthepatectomy liver failure (PHLF) and 90-day mortality was compared. Results Patients with no, mild, moderate, and severe cirrhosis accounted for 15.9%, 29.2%, 35.9%, and 19.0%, respectively, in the entire cohort. ICG-R15 was found to be less than 10% in 100%, 93.3%, 86.3%, and 70.1% of the patients with no, mild, moderate, and severe cirrhosis, respectively. There was only a weak correlation between ICG-R15 and the pathological severity of liver cirrhosis (r = 0.325; P < 0.001). However, CSS showed a strong correlation with the pathological severity of liver cirrhosis (r = 0.788; P < 0.001). For those with ICG-R15 in the normal range, the accuracy of CSS in diagnosing no/mild, moderate, and severe cirrhosis was 89.1%, 72.8%, and 72.1%, respectively. In addition, CSS was superior to ICG-R15 in predicting PHLF and 90-day mortality. Conclusions CSS was more useful than ICG-R15 in the preoperative assessment of cirrhotic severity in HCC patients with Child-Pugh grade A liver function. More studies are needed to further validate CSS in patients with different Child-Pugh grades.