An embodiment of the invention discloses a stable-control blasting method for open-pit mine slopes, which relates to the technical field of exploitation of open-pit mines and is invented for solving the problem that damage of the slopes by blast vibration needs to be relieved so that the open-pit mine slopes can be highly stabilized. The method includes: quantity of priming explosive of a largest section in a blasting area close to an open-pit mine slope is limited; and delay time for open bench blast control rows of the blasting area close to the slope and blast holes corresponding to all the control rows are 1-4ms per hole-pitch meter, and delay time for rowed blast holes is 10-30ms per row-spacing meter. The stable-control blasting method is applicable to open-pit mining, and also applicable to hydropower engineering, excavation of large-sized underground workshop chambers, cutting engineering and the like, which need slope maintenance.