The invention relates to a method and a software product for controlling percussive rock drilling, and further to a rock drilling rig to which the method is applied. The invention comprises monitoring the rotation resistance, the aim being to keep it below a desired reference value. To adjust the rotation resistance, successive control actions may be carried out, such as decreasing the feed force, decreasing the percussion power and stopping the feed. Control actions are started once a limit set for the control has been exceeded. At least one limit is a time limit determining the time difference between two successive control functions.