In a control information receiving method, a second device receives m control channels from a first device. Control information carried on the m control channels corresponds to a same hybrid automatic repeat request (HARQ) process and is consecutive control information of the HARQ process, control information carried on each of the m control channels includes false alarm indication information, and m is a positive integer greater than or equal to 2. The second device determines, based on a combined state of false alarm indication information carried on the m control channels, whether there is a false alarm in control information carried on at least one of the m control channels.