The Four-day Workweek refers to a working hour system of four days or 32 hours per week. From 2015 to 2022, major developed capitalist countries in Europe, Oceania, North America, and Asia have implemented experiments of shortened working hours, represented by the Four-day Workweek, to varying degrees. Organizers and researchers of the Four-day Workweek Campaign have put forward theoretical propositions from three perspectives: economy, labor-capital relations, and society. The Four-day Workweek is essentially a measure taken by capitalist countries and enterprises to cope with the economic challenges of capitalism by shortening working hours. However, it faces the challenges of insuffi cient long-term sustainability and susceptibility to setbacks. The Four-day Workweek provides two implications for China: fi rst, we should improve the three-party negotiation and coordination mechanism in labor relations, enhancing workers' bargaining power, steadily reducing working hours, and safeguarding workers' legitimate rights and interests; second, we should be cautious of the "trap of shortened workweek" set by developed capitalist countries in the future when considering further reductions in working hours