Etanercept is an anti-tumor necrosis factor ɑ (anti-TNFɑ) drug used for treating immunomediated inflammatory diseases. It is least associated with hepatitis B virus (HBV) reactivation. We present a 71-year-old man with psoriasis refractory to phototherapy and acitretin, which led to etanercept monotherapy. Before anti-TNFɑ treatment, past contact with HBV was elicited; antibodies to HBc and HBs were positive whereas HBsAg was negative. Seven years after treatment initiation, while the patient was completely asymptomatic, a transaminase elevation was found and a reactivation of HBV was documented, with a high viral load of the virus. He started entecavir therapy and, after a 14-month follow-up, the viral load is still detectable at a low level, as well as HBsAg. We emphasize the late and asymptomatic reactivation of HBV associated with soluble anti-TNFɑ monotherapy. This case reinforces the importance of current recommendations for periodic monitoring of viral load and HBV markers in all patients that have had prior contact with HBV (positive anti-HBc), with or without indication for treatment of HBV (HBsAg and HBV-DNA negative).