A rotary compressor (2, 200) comprising: a case configured to store a lubricating oil; a rotary shaft (31, 225) disposed inside the case, and having an eccentric portion (51, 231, 232, 233); a compression mechanism having a cylinder (41, 201, 202, 203) accommodating the eccentric portion (51, 231, 232, 233), a main bearing configured to rotatably support the rotary shaft (31, 225) from above the cylinder (41, 201, 202, 203), and an auxiliary bearing configured to rotatably support the rotary shaft (31, 225) from below the cylinder (41, 201, 202, 203); a balancer attached to the rotary shaft (31, 225) at a position below the auxiliary bearing; and a balancer cover (81, 230, 240) configured to cover the balancer from below, wherein a through-hole (84, 245) is formed at a position of the balancer cover (81, 230, 240) facing the rotary shaft (31, 225) in an axial direction, and the rotary shaft (31, 225) includes a thrust sliding portion configured to come into contact with a seal (82, 242a) located around the through-hole (84, 245) of the balancer cover (81, 230, 240), in the axial direction, thereby blocking communication between the inside and the outside of the balancer cover (81, 230, 240) through the through-hole (84, 245), characterized in that the rotary shaft (31, 225) further includes a protruding portion (87, 227) located on an inner peripheral side of the thrust sliding portion, and protruding downward from a lower end of the through-hole (84, 245) through the through-hole (84, 245), and a supply channel open on a lower end surface of the protruding portion (87, 227) to guide the lubricating oil, wherein the rotary shaft (31, 225) is displaceable by a predetermined distance in the axial direction with respect to the compression mechanism, and the protruding portion (87, 227) protrudes from the lower end of the through-hole (84, 245) to be longer than the predetermined distance. a case configured to store a lubricating oil; a rotary shaft (31, 225) disposed inside the case, and having an eccentric portion (51, 231, 232, 233); a compression mechanism having a cylinder (41, 201, 202, 203) accommodating the eccentric portion (51, 231, 232, 233), a main bearing configured to rotatably support the rotary shaft (31, 225) from above the cylinder (41, 201, 202, 203), and an auxiliary bearing configured to rotatably support the rotary shaft (31, 225) from below the cylinder (41, 201, 202, 203); a balancer attached to the rotary shaft (31, 225) at a position below the auxiliary bearing; and a balancer cover (81, 230, 240) configured to cover the balancer from below, wherein a through-hole (84, 245) is formed at a position of the balancer cover (81, 230, 240) facing the rotary shaft (31, 225) in an axial direction, and the rotary shaft (31, 225) includes a thrust sliding portion configured to come into contact with a seal (82, 242a) located around the through-hole (84, 245) of the balancer cover (81, 230, 240), in the axial direction, thereby blocking communication between the inside and the outside of the balancer cover (81, 230, 240) through the through-hole (84, 245), characterized in that the rotary shaft (31, 225) further includes a protruding portion (87, 227) located on an inner peripheral side of the thrust sliding portion, and protruding downward from a lower end of the through-hole (84, 245) through the through-hole (84, 245), and a supply channel open on a lower end surface of the protruding portion (87, 227) to guide the lubricating oil, wherein the rotary shaft (31, 225) is displaceable by a predetermined distance in the axial direction with respect to the compression mechanism, and the protruding portion (87, 227) protrudes from the lower end of the through-hole (84, 245) to be longer than the predetermined distance.