An engine system includes: an exhaust path through which an exhaust gas of an engine passes; an urea injection valve that injects urea into the exhaust path; a catalyst that is provided in the exhaust path on a downstream of the urea injection valve, and that selectively reduces NOx by using ammonia acting as a reducing agent, the ammonia being generated by hydrolyzing injected urea from the urea injection valve; a heating portion that is capable of heating the catalyst and the injected urea; and a control unit that performs first control, in which the urea injection valve injects urea, the heating portion heats the injected urea to generate ammonia, or second control, in which the heating portion increases a temperature of the catalyst to a temperature at which NOx can be reduced, on a basis of an amount of ammonia adsorbed on the catalyst.