An engine system is capable of switching between a first fuel injection mode, in which fuel is injected from a fuel injection valve 23 directly into a combustion chamber 6 in the compression stroke, and a second fuel injection mode, in which fuel is injected from the fuel injection valve 23 directly into the combustion chamber 6 in the intake stroke. A controller 30 determines the characteristic of the fuel that is supplied to the fuel injection valve 23, selects either the first fuel injection mode or the second fuel injection mode according to the fuel characteristic, and starts an engine 1 in the selected fuel injection mode.