The invention discloses a method and a device for developing, belonging to the display field. The method comprises the following steps of obtaining an exposure interval variation of a first position, wherein the first position is a projection position of a second position on a mask and the second position is a position on a substrate; determining flow of developing solution which is sprayed to the second position according to the exposure interval variation; and spraying the developing solution to the second position according to the flow, wherein the developing solution is used for etching an organic material arranged at the second position. The device comprises an obtaining module, a determining module and a spraying module. According to the method and the device for developing, the line widths of graphs can be uniform.