A closed motor-driven compressor includes a closed vessel containing a lubricating oil collected in a bottom portion thereof, a compression section accommodated in the closed vessel, and a motor section accommodated in the closed vessel for driving the compression section. The compression section includes a crankshaft driven by the motor section and having a lower end submerged in the lubricating oil, and a block for rotatably supporting the crankshaft. The block has a cylinder formed therewith and having an open end. The block also has a rib formed therewith, a generally flat shoulder portion formed on one side of the cylinder, and a leg formed below the generally flat shoulder portion. The compression section also includes a cylinder head secured to the rib for covering the open end of the cylinder. An oil guide is formed with the block for guiding to the bottom portion of the closed vessel a lubricating oil that is sucked up from the lower end of the crankshaft, caused to spout out from the upper end of the crankshaft, and collected on the generally flat shoulder portion. The oil guide prevent the oil from dropping on and flowing over a suction muffler disposed below the rib, and also prevents the oil from dropping directly on the bottom portion of the closed vessel.