The Japan Integrated Staging Score (JIS Score), introduced by Kudo et al. in 2003, combines Child-Pugh grade and Japanese TNM criteria to enhance liver cancer staging. It addresses LCSGJ’s deficiency (Liver Cancer Study Group of Japan) by including liver function evaluation. Scores are assigned based on Child-Pugh grades (0, 1, 2 for A, B, C) and TNM stages (0-3). Patients are grouped (0-5) according to their total scores. Significant survival differences exist between JIS scores, with JIS 0 having a higher 10-year survival rate (65%) than CLIP (23%). The JIS score shows better prognostic stratification than CLIP and BCLC systems, especially for early-diagnosed HCC. Although developed with Japanese patients, validation studies are needed for Western populations. Limitations of LCSGJ staging, like inaccurate size weighting and lack of pathology information, persist.