Host cell metabolism can be modulated by viral infection, affecting viral survival or clearance. Yet the cellular metabolism rewiring mediated by the N-6-methyladenosine (m(6)A) modification in interactions between virus and host remains largely unknown. Here we report that in response to viral infection, host cells impair the enzymatic activity of the RNA m(6)A demethylase ALKBH5. This behavior increases the m(6)A methylation on alpha-ketoglutarate dehydrogenase (OGDH) messenger RNA (mRNA) to reduce its mRNA stability and protein expression. Reduced OGDH decreases the production of the metabolite itaconate that is required for viral replication. With reduced OGDH and itaconate production in vivo, Alkbh5-deficient mice display innate immune response-independent resistance to viral exposure. Our findings reveal that m(6)A RNA modification-mediated down-regulation of the OGDH-itaconate pathway reprograms cellular metabolism to inhibit viral replication, proposing potential targets for controlling viral infection.