A planetary gear assembly for a drum washing machine and a washing machine are provided. The planetary gear assembly includes a planetary gear component. The planetary gear component includes a planet carrier, a plurality of planetary gears rotatably mounted to the planet carrier separately and configured to be meshed with a main shaft separately, the main shaft being configured to drive a drum to rotate in a drum washing machine; and a planetary gear outer teeth casing fitted over an outer side of the plurality of planetary gears, meshed with the plurality of planetary gears separately, and configured to be in transmission connection with an agitator in the drum.