This retrospective study investigated preliminarily the prognostic value of body composition parameters derived from baseline F-FDG PET/CT in angioimmunoblastic T-cell lymphoma (AITL) patients. We included 94 treatment-naïve AITL patients diagnosed by histopathology. Based on the axial CT images of the third lumbar vertebra, the areas of skeletal muscle (SM), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) were semi-automatically delineated and standardized to finally obtain SM index (SMI), VAT index (VATI), and SAT index (SATI). Body composition density characterized by CT attenuation was obtained, including SM density (SMD), VAT density (VATD), and SAT density (SATD). Besides, the maximum standardized uptake value (SUVmax), total metabolic tumor volume (TMTV), and total lesion glycolysis (TLG) were also calculated. Endpoints included progression-free survival (PFS) and overall survival (OS). Survival curves and Cox regression analysis were performed‌‌.Of 94 AITL patients(mean age:63.4 ± 9.7 years,67% men), 65 progressed and 55 died[median follow-up: 27.5 (10.5-45.7) months].High baseline C-reactive protein level [hazard ratio (HR) = 2.47, 95%CI: 1.37-4.45, p = 0.003), low SMD (HR = 2.18, 95%CI:1.29-3.69, p = 0.003), high SATD (HR = 1.92, 95%CI: 1.05-3.54, p = 0.035), and low VATI (HR = 1.95, 95%CI: 1.12-3.38, p = 0.018) were independent risk factors for poor PFS. AITL score>2(HR = 2.90, 95%CI: 1.59-5.29, p < 0.001), sarcopenia(HR = 1.78, 95%CI: 1.01-3.12,p = 0.045), low VATI(HR = 2.24,95%CI: 1.27-3.95,p = 0.005), and high TMTV(HR = 2.46, 95%CI: 1.37-4.40, p = 0.003) may serve as independent risk factors for poor OS. In conclusion, in addition to conventional TMTV, body composition parameters derived from baseline F-FDG PET/CT may offer preliminary prognostic value for AITL patients.