Abstract: To investigate the influence of heel height on the patellofemoral joint mechanics of young women during stair descent, the Vicon infrared three-dimensional motion capture system and a three-dimensional force platform were used to synchronously collect kinematic and kinetic data of the knee joints from 25 young women descending stairs while wearing high-heeled shoes with four different heights (1, 3, 5 and 7 cm). Digital formulas were adopted to calculate indexes such as the patellofemoral joint stress and patellofemoral joint reaction force of young women. The data were statistically analyzed by using one-way repeated measures ANOVA. The results showed that compared with the flat heel condition, significant increase was observed in the second peak of patellofemoral joint stress, patellofemoral joint reaction force, quadriceps force and knee extension moment in the high heel, medium heel, and low heel conditions. Therefore, when women descend stairs, wearing high-heeled shoes with a heel height of less than 3 cm can effectively reduce the patellofemoral joint reaction force and patellofemoral joint stress, which may help to decrease the likelihood of patellofemoral joint pain.