Perspective in the composition of the Mona Lisa plays a crucial role in creating depth and realism in the painting. Leonardo da Vinci used a technique called linear perspective to give the illusion of three-dimensional space on a two-dimensional surface. This technique is evident in the way the background gradually recedes behind the subject, giving a sense of distance and depth to the painting. This use of perspective helps draw the viewer's eye towards the central figure of the Mona Lisa, making her the focal point of the composition.