A method for producing propylene oxide, the method comprising the following steps to: Oxidation step: a step of obtaining a reaction mixture containing cumene hydroperoxide by contacting cumene with an oxygen-containing gas to cause a reaction between cumene and oxygen in the gas, wherein the oxidation reaction temperature is 50°C to 200°C and wherein the cumene hydroperoxide content of the reaction mixture containing cumene hydroperoxide is 5 to 80 wt% per 100 wt% of the reaction mixture; Distillation step: a step of distilling the reaction mixture containing cumene hydroperoxide obtained in the oxidation step to be separated into a concentrate containing cumene hydroperoxide and a distillate, wherein the reaction mixture is continuously distilled under a condition where a ratio of a flow rate of the distillate to a flow rate of the reaction mixture to be distilled, D/F, is 0.037 or more and 0.13 or less, provided that the flow rate of the reaction mixture is a weight of the reaction mixture distilled per unit time, whereas the flow rate of the distillate is a weight of the distillate distilled off per unit time, wherein the distillation is performed at a distillation column, and wherein the column top temperature of the distillation column is in the range of 30 to 150°C, and the column bottom temperature of the distillation column is in the range of 30 to 150°C; Epoxidation step: a step of obtaining a reaction mixture containing propylene oxide and cumyl alcohol by contacting the concentrate containing cumene hydroperoxide obtained in the distillation step with propylene in the presence of a catalyst in one or more reactors to cause a reaction between propylene and cumene hydroperoxide in the concentrate, wherein an outlet temperature of the final reactor of the one or more reactors is adjusted to 115°C or more and less than 140°C; and Separation step: a step of separating crude propylene oxide by distilling the reaction mixture containing propylene oxide and cumyl alcohol obtained in the epoxidation step. Oxidation step: a step of obtaining a reaction mixture containing cumene hydroperoxide by contacting cumene with an oxygen-containing gas to cause a reaction between cumene and oxygen in the gas, wherein the oxidation reaction temperature is 50°C to 200°C and wherein the cumene hydroperoxide content of the reaction mixture containing cumene hydroperoxide is 5 to 80 wt% per 100 wt% of the reaction mixture; Distillation step: a step of distilling the reaction mixture containing cumene hydroperoxide obtained in the oxidation step to be separated into a concentrate containing cumene hydroperoxide and a distillate, wherein the reaction mixture is continuously distilled under a condition where a ratio of a flow rate of the distillate to a flow rate of the reaction mixture to be distilled, D/F, is 0.037 or more and 0.13 or less, provided that the flow rate of the reaction mixture is a weight of the reaction mixture distilled per unit time, whereas the flow rate of the distillate is a weight of the distillate distilled off per unit time, wherein the distillation is performed at a distillation column, and wherein the column top temperature of the distillation column is in the range of 30 to 150°C, and the column bottom temperature of the distillation column is in the range of 30 to 150°C; Epoxidation step: a step of obtaining a reaction mixture containing propylene oxide and cumyl alcohol by contacting the concentrate containing cumene hydroperoxide obtained in the distillation step with propylene in the presence of a catalyst in one or more reactors to cause a reaction between propylene and cumene hydroperoxide in the concentrate, wherein an outlet temperature of the final reactor of the one or more reactors is adjusted to 115°C or more and less than 140°C; and Separation step: a step of separating crude propylene oxide by distilling the reaction mixture containing propylene oxide and cumyl alcohol obtained in the epoxidation step.