The present invention relates to the field of automobiles. Provided are a method for adjusting constant speed cruising according to a speed limit, and constant speed cruising. The method comprises: recording a speed limit matching a vehicle road; detecting the road a vehicle is currently driving on; and according to a speed limit matching the road the vehicle is currently driving on, when a user uses a constant speed cruising function and a constant speed cruising set speed is higher than the speed limit matching the road the vehicle is currently driving on, adjusting the constant speed cruising speed to be the speed limit matching the current driving road. According to the present invention, by pre-setting a speed limit matching a vehicle driving road, when a vehicle is driving on the road, a constant speed cruising function is set according to the speed limit of the road, so that the constant speed cruising is more intelligent. Moreover, driving safety is increased, and speeding is prevented.