To assess the ability of restaging positron emission tomography (PET) scanning to predict clinical outcome after first‐line treatment in patients with Hodgkin's disease, we included 60 patients with histologically proven HD, who underwent whole‐body [¹⁸F]‐fluorodeoxygenase ([¹⁸F]‐FDG)‐PET studies after first‐line treatment and with a follow‐up of at least 1 year. Persistence or absence of residual disease on PET was related to progression‐free survival (PFS) using Kaplan–Meier survival analysis. After treatment, 55 patients showed a normal [¹⁸F]‐FDG‐PET scan; 50 of 55 remained in complete remission (CR), with a median follow‐up of 955 d. Only five patients relapsed (median PFS, 296 d). During follow‐up in all five patients, [¹⁸F]‐FDG‐PET was the first tool that became positive for relapse. Persistent abnormal [¹⁸F]‐FDG uptake was seen in only five patients; all of them relapsed (median PFS, 296 d). In four of five patients, only PET predicted persistent disease. All relapses were proven histologically. Two‐year actuarial PFS rate for negative patients was 91% compared with 0% for positive patients. We concluded that [¹⁸F]‐FDG‐PET has an important prognostic role in the post‐treatment evaluation of HD patients.