In a hydraulic chain tensioner having a housing, a hollow plunger slidable in a plunger-accommodating hole in the housing, and a hollow sleeve extending into the plunger from a bottom of the plunger-accommodating hole, and a check valve mounted at the opposite end of the sleeve, a passage is provided on the outer surface of the sleeve to accelerate the balance of pressure between a first high pressure chamber between the check valve and the protruding end of the plunger and a second high pressure chamber between the inner end of the plunger and the bottom of the plunger-accommodating hole. In an alternative embodiment, balance is accelerated by communication between the second high pressure chamber and an oil reservoir inside the sleeve on the upstream side of the check valve.