The invention discloses an urban mapping method and device. The urban mapping method comprises the following steps of receiving a remote sensing image of a target city input by a user and obtaining remote sensing image data; obtaining a target vegetation index of the remote sensing image based on the remote sensing image data; receiving original light data of the target city input by the user; carrying out normalization and re-sampling processing on the original light data to obtain target light data; obtaining a city index based on the target vegetation index and the target light data; and carrying out mapping based on the city index to obtain a city effect drawing of the target city. The urban mapping method has simple and convenient processing process, high automation degree and high processing efficiency and does not need a complicated preprocessing process; and furthermore, the city index is obtained based on the target vegetation index and the target light data, the city index is utilized to carry out mapping, the mapping effect is good, the precision is high and the method is easy to popularize and apply.