A plasma processing apparatus and a method of manufacturing a semiconductor device which can prevent a discharge from occurring between a substrate such as a semiconductor wafer or the like, and a base material of a lower electrode or a peripheral structure of the base material, and can improve yield and productivity. The plasma processing apparatus includes a processing chamber, a lower electrode, an upper electrode, and a plurality of lifter pins for supporting a substrate to be processed. Each of the lifter pins includes a pin body part and a lid part which is disposed on a top portion of the pin body part and has an outer diameter greater than an outer diameter of the pin body part. The lower electrode includes through-holes for lifter pins each of which includes a pin body receiving part, which has an inner diameter less than the outer diameter of the lid part and receives the pin body part, and a lid receiving part, which is formed in an upper portion of the pin body receiving part and receives the cover portion, and in which the lifter pins are disposed. In a state where the lifter pins are lowered, the lid part is received in the lid receiving part, and the upper portion of the pin body receiving part is blocked by the lid part.