Objective To investigate the distribution pattern of Traditional Chinese Medicine TCM syndromes in patients with cancer- associated malnutrition and analyze the correlation between these syndrome types and immune - inflammatory indicators. Method A cross-sectional study was conducted from August 2022 to January 2025 at the Oncology Department of Wangjing Hospital Chinese Academy of Traditional Chinese Medicine. A standardized questionnaire was used to collect general information nutrition impact symptoms physical examination indicators and immune - inflammatory indicators from 191 patients diagnosed with CAM. Descriptive frequency analysis was performed for NIS the distribution of major TCM syndrome types was summarized based on factor analysis and cluster analysis and intergroup difference analysis of immune-inflammatory indicators among different TCM syndrome types in CAM patients was conducted. Result Among the 191 CAM patients xerostomia anorexia and nausea had the highest frequencies of occurrence with 130 126 and 96 cases respectively. Factor analysis of 11 symptoms identified 4 common factors with a cumulative contribution rate of 59. 63%. Results of cluster analysis showed that TCM syndrome types were classified into three categories spleen-stomach yin deficiency syndrome spleen-stomach qi deficiency syndrome and spleen deficiency with dampness accumulation syndrome. Statistically significant differences P<0. 05 were observed in triceps skinfold thickness total protein white blood cells count and systemic immune-inflammation index among the three syndrome types. Secondary analysis revealed that TSF in patients with spleen deficiency with dampness accumulation syndrome was lower than that in patients with spleen-stomach qi deficiency syndrome TP appetite visual analog scale score neutrophils and SII in patients with Spleen-stomach qi deficiency syndrome were higher than those in patients with spleen - stomach yin deficiency syndrome while the PG- SGA score was lower all P< 0. 05 . Conclusion This study found that the main TCM syndrome types in CAM patients are spleen - stomach yin deficiency syndrome spleen-stomach qi deficiency syndrome and spleen deficiency with dampness accumulation syndrome. Patients with spleen-stomach yin deficiency syndrome have the most severe CAM patients with spleen - stomach qi deficiency syndrome present a more severe inflammatory state and patients with spleen deficiency with dampness accumulation syndrome show the most significant reduction in muscle mass. In conclusion for CAM patients TCM treatment should be based on " strengthening the spleen " combined with replenishing qi nourishing yin and resolving dampness to regulate immune-inflammatory levels and improve malnutrition.