PURPOSE: To send identical oil amount with a half of prior stroke of a plunger by inserting a pair of opposed plungers in one plunger barrel and driving these plungers with separate cams respectively.

CONSTITUTION: When a pair of cams 4 are rotated synchronously in the same direction, rollers 16 are driven by these cams to reciprocate vertically and a pair of plungers 3 slide vertically synchronously so that fuel is forcibly sent from a pipe 9 to a fuel gallery 8. Thus, the fuel is supplied from a fuel supply hole 2b into a plunger barrel 2 and compressed by a pair of plungers 3 to be sent from a central portion 2a to a delivery valve 5. Further, high pressure fuel is sent to an injection pipe 6 and injected into a combustion chamber of engine. Thus since a pair of plungers 3 approach each other vertically within the plunger barrel 2 with identical stroke and timing, a half of prior stroke of each plunger 3 will do to send same amount of oil as prior one.