The present invention provides a fuel injection control device of a saddle-ride type vehicle that can rapidly reflect an acceleration request of the user with the number of parts reduced as with the related art although making a stroke determination of the internal combustion engine by a crank pulse. The fuel injection control device includes a throttle opening read timing setter (162) that sets the timing at which a throttle opening (TH) is read. The throttle opening read timing setter (162) is triggered to detect the throttle opening (TH) used for calculation of a basic injection amount by the start of calculation timing of the basic injection amount (FICAL) if the injection amount calculation timing (FICAL) is at the position corresponding to a toothless part (24) of a crank pulsar rotor (20). The throttle opening read timing setter (162) detects the throttle opening TH based on crank pulse interrupt according to a crank pulse (PCP) if the injection amount calculation timing (FICAL) is at a position other than the position corresponding to the toothless part (24).