Objective To assess the predictive value of 18F-fluorodeoxyglucose (FDG) PET/CT imaging and relevant factors in the prognosis of patients with classic Hodgkin lymphoma (cHL) before or after autologous stem cell transplantation (ASCT). Methods From January 2008 to June 2017, 55 cHL patients (28 males, 27 females; age: (28.8±9.6) years) confirmed by pathology in Shanghai General Hospital were retrospectively included. 18F-FDG PET/CT imaging was performed before ASCT in 43 cases and after ASCT in 34 cases (22 patients underwent the imaging both before and after ASCT). Patients were divided into positive group (≥4) and negative group (<4) according to 18F-FDG PET/CT imaging results using Deauville 5-point scale. The predictive value of relevant factors in the prognosis was evaluated with progression-free survival (PFS) and overall survival (OS) using Kaplan-Meier survival analysis and log-rank test. Hazard ratio (HR) was calculated by Cox regression model. Results Of 55 cHL patients, 29 (53%) had a progression of disease after a median follow-up of 8 months, and 11 (20%) patients died after a median follow-up of 29.5 months, with the 3-year PFS rate of 46.4% and OS rate of 84.5%. Significant differences of PFS rate were found between patients with or without B symptoms, between patients with or without large mediastinal mass, between patients with international prognostic score (IPS) of 0-2 and those with IPS of 3-7, among patients with different effect of salvage chemotherapy (complete remission (CR), partial remission (PR) + stable disease (SD), progressive disease (PD)), and between patients with negative or positive PET/CT imaging results before or after ASCT (χ2 values: 5.52-20.01, HR: 2.21(95% CI: 1.56-3.12)-5.51(95% CI: 1.86-16.33), all P<0.05). B symptoms and large mediastinal mass were also prognostic factors for OS rate (HR: 5.28(95% CI: 1.14-24.51) and 4.27(95% CI: 1.24-14.79), both P<0.05). The combination of 18F-FDG PET/CT imaging before and after ASCT was statistically significant for predicting PFS (χ2=11.28, P<0.01). Multivariate survival analysis showed that the risk of progression in patients with positive PET/CT results after ASCT was significantly higher than those with negative results (HR=6.20, P<0.01), and the risk of death in patients with B symptoms was significantly higher than those without B symptoms (HR=5.28, P<0.05). Conclusion 18F-FDG PET/CT imaging results after ASCT have important values for predicting PFS in cHL patients after ASCT, and B symptoms can be used as an important prognostic indicator of OS after ASCT. Key words: Lymphoma; Stem Cells; Transplantation, autologous; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose