Provided are an electronic device and method for assisting with driving of a vehicle, the electronic device including: a sensing unit configured to sense a driving state of at least one external vehicle on an entry scheduled lane that the vehicle is to enter by changing lanes; a processor configured to determine an entry possible region on the entry scheduled lane based on the sensed driving state of the at least one external vehicle and determine an entry condition for entry of the vehicle into the entry possible region; and an outputter configured to output information about the entry possible region and the entry condition.