A method of controlling illuminance of a target area in a lighting system, wherein the lighting system comprises at least one light source (110, 120, 130, 140, 150) and each of the at least one light source (110, 120, 130, 140, 150) comprises a plurality of light modules (I1-I10), each of the plurality of light modules (I1-I10) being adjustable independently, wherein different light modules within each of the at least one light source (110, 120, 130, 140, 150) differ in terms of lighting direction, the method comprising: selecting at least one light module, which is associated with the illuminance of the target area, from the at least one light source (110, 120, 130, 140, 150) based on position relationships between each of the at least one light source and the target area and lighting distributions of each of the at least one light source (110, 120, 130, 140, 150); and adjusting at least one of the selected at least one light module, characterized in that the selecting of at least one light module comprises: obtaining the position relationships between each of the at least one light source (110, 120, 130, 140, 150) and the target area, each position relationship representing a relationship between a position of a respective light source and a position of the target area; obtaining the lighting distributions of the at least one light source (110, 120, 130, 140, 150), each lighting distribution referring to a light intensity of a respective light source in respective directions; obtaining, from the position relationships, a relative direction of the target area from a light source; obtaining, from the lighting distribution of the light source, lighting directions of a plurality of light modules emitting from the light source; comparing the relative direction with the lighting directions; and selecting at least one light module from the plurality of light modules of the light source based on the comparison results. selecting at least one light module, which is associated with the illuminance of the target area, from the at least one light source (110, 120, 130, 140, 150) based on position relationships between each of the at least one light source and the target area and lighting distributions of each of the at least one light source (110, 120, 130, 140, 150); and adjusting at least one of the selected at least one light module, obtaining the position relationships between each of the at least one light source (110, 120, 130, 140, 150) and the target area, each position relationship representing a relationship between a position of a respective light source and a position of the target area; obtaining the lighting distributions of the at least one light source (110, 120, 130, 140, 150), each lighting distribution referring to a light intensity of a respective light source in respective directions; obtaining, from the position relationships, a relative direction of the target area from a light source; obtaining, from the lighting distribution of the light source, lighting directions of a plurality of light modules emitting from the light source; comparing the relative direction with the lighting directions; and selecting at least one light module from the plurality of light modules of the light source based on the comparison results.