The purpose of this study is to investigate the anti-inflammatory effect of thalidomide (Thd) on H1N1-induced acute lung injury in mice. BALB/C mice were infected intranasally with influenza A virus (H1N1) and then treated with Thd at a dose of 100 or 200 mg/kg/day for 7 days. Weight loss and survival of mice were monitored for 14 days after virus challenge, and the serum and lung tissues were collected at 4 days for histological and biochemical analysis. The results showed that Thd significantly improved the survival rate, reduced the infiltration of inflammatory cells and cytokine (e.g., IL-6, TNF-α) and chemokine (e.g., RANTES, IP-10) levels, and inhibited activated p-NFκB p65 in infected mice. These findings suggested that Thd may attenuate H1N1-induced pulmonary injury and thus may find use in the treatment of viral diseases.