An exposure apparatus comprises a light source (1) and a diffusing sheet (2) provided below the light source (1), a side of the diffusing sheet (2) adjacent to the light source (1) is an incident face (21) and the other side opposite to the incident face (21) is an emitting face (22); the light emitted from the light source (1) enters the diffusing sheet (2) through the incident face (21), is refracted within the diffusing sheet (2), and after being diffused, emits out evenly throughout the emitting face (22). The exposure apparatus enables an evenly exposure of the photoresist on the substrate. An exposure method using such an exposure apparatus is also disclosed.