The 2020 Sioux Chief PowerPEX 200 was the 18th stock car race of the 2020 ARCA Menards Series, the tenth and final race of the 2020 Sioux Chief Showdown, and the fourth iteration of the event. The race was held on Saturday, September 26, 2020, in Memphis, Tennessee, at Memphis International Raceway, a 3⁄4 mile (1.2 km) tri-oval short track. The race took the scheduled 200 laps to complete. At race's end, Ty Gibbs of Joe Gibbs Racing would hold off the field on the final restart with three to go to win his eighth career ARCA Menards Series win and his sixth and final win of the season. Meanwhile, second-place finisher, GMS Racing driver Sam Mayer, would narrowly hold off Gibbs by 5 points to win the inaugural Sioux Chief Showdown championship.