Objective To evaluate the nutritional status of patients with primary liver cancer and to compare the ability of PG-SGA and mPG-SGA to assess malnutrition. Method Clinical data of 249 patients diagnosed with primary liver cancer for the first time at Affiliated Hospital of Southwest Medical University between April 2022 and September 2023 were collected. PG-SGA and mPG-SGA were used to assess the nutritional status of patients. Spearman correlation analysis was used to compare the correlation between different nutritional indicators and two scales. The ROC curve was used to evaluate the accuracy of mPG-SGA. The Kappa coefficients were used to evaluate the concordance between two scales. Result Among 249 patients with primary liver cancer 196 78. 71% and 189 75. 90% were diagnosed with moderate to severe malnutrition using PG - SGA and mPG - SGA respectively. Using PG-SGA as a criterion mPG-SGA showed good accuracy for good / mild malnutrition moderate malnutrition and severe malnutrition with AUC values of 0. 982 0. 938 and 0. 977 respectively P < 0. 001 . It also showed almost perfect consistency with PG-SGA Kappa = 0. 951 P<0. 001 . Analysis by gender age history of smoking alcohol consumption clinical stage and body mass index BMI subgroups revealed that mPG-SGA showed strong consistency for good / mild malnutrition moderate malnutrition and severe malnutrition among patients with BMI < 18. 5 kg / m 2 Kappa = 0. 762 P = 0. 001 . All subgroups with the exception of BMI<18. 5 kg / m 2 showed almost perfect consistency for the three different nutritional stages Kappa>0. 9 P<0. 001 . Conclusion Malnutrition is prevalent in patients with primary liver cancer. mPG-SGA has been shown to have good accuracy and concordance with PG-SGA. It is a simpler tool for assessing malnutrition in patients with primary live cancer.