The intake system includes an intake path forming section having a downstream end in communication with an intake port included in each of cylinder heads of a pair of banks of an engine main body. The intake path connects to the common air chamber with an upstream end of the intake path being open in the air chamber. A fuel injection valve for injecting fuel toward the upstream end opening portion of each intake path is disposed in the air chamber. A path forming member constituting at least part of an intake path forming section by forming an upstream end of an intake path is connected to a first wall portion of an air chamber. A fuel injection valve is mounted from the outside in a second wall portion of the air chamber opposing the first wall portion with a leading end portion facing an inside of the air chamber.