A scroll compressor, comprising: a housing in which an interior space is divided into a first chamber and a second chamber; a scroll compression mechanism which includes a fixed scroll and an orbiting scroll disposed in the first chamber and compresses a refrigerant between the fixed scroll and the orbiting scroll to cause the compressed refrigerant to flow into the second chamber; a rotary shaft which is a rod-shaped member, includes an oil supply passage which extends in a longitudinal direction of the rod-shaped member and through which lubricant oil passes, and causes the orbiting scroll disposed on an outlet side of the oil supply passage to orbit; a back pressure chamber which is disposed on the rotary shaft side of the orbiting scroll and into which the lubricant oil flowing out from the oil supply passage flows; an oil drain passage through which the lubricant oil flowing into the back pressure chamber passes to be discharged to the first chamber; a flow control mechanism for changing a flow rate of the lubricant oil flowing through the oil drain passage; and an oil supply pump which is installed in the oil supply passage and supplies the lubricant oil stored in the first chamber to the back pressure chamber, characterized in that the flow control mechanism increases the flow rate of the lubricant oil flowing through the oil drain passage in a case where an orbital speed of the orbiting scroll is larger than a threshold value compared to a case where the orbital speed of the orbiting scroll is equal to or smaller than the threshold value, and the threshold value is equal to or larger than an orbital speed equivalent to a case where the scroll compressor is operated with a capacity of 1/2 of a rated operation and is equal to or smaller than an orbital speed equivalent to a case where the scroll compressor is operated with the capacity of the rated operation. a housing in which an interior space is divided into a first chamber and a second chamber; a scroll compression mechanism which includes a fixed scroll and an orbiting scroll disposed in the first chamber and compresses a refrigerant between the fixed scroll and the orbiting scroll to cause the compressed refrigerant to flow into the second chamber; a rotary shaft which is a rod-shaped member, includes an oil supply passage which extends in a longitudinal direction of the rod-shaped member and through which lubricant oil passes, and causes the orbiting scroll disposed on an outlet side of the oil supply passage to orbit; a back pressure chamber which is disposed on the rotary shaft side of the orbiting scroll and into which the lubricant oil flowing out from the oil supply passage flows; an oil drain passage through which the lubricant oil flowing into the back pressure chamber passes to be discharged to the first chamber; a flow control mechanism for changing a flow rate of the lubricant oil flowing through the oil drain passage; and an oil supply pump which is installed in the oil supply passage and supplies the lubricant oil stored in the first chamber to the back pressure chamber, characterized in that the flow control mechanism increases the flow rate of the lubricant oil flowing through the oil drain passage in a case where an orbital speed of the orbiting scroll is larger than a threshold value compared to a case where the orbital speed of the orbiting scroll is equal to or smaller than the threshold value, and the threshold value is equal to or larger than an orbital speed equivalent to a case where the scroll compressor is operated with a capacity of 1/2 of a rated operation and is equal to or smaller than an orbital speed equivalent to a case where the scroll compressor is operated with the capacity of the rated operation.