The invention relates to a method for inserting advertisements in a live video of a digital television. An operation server obtains a plurality of composing elements in any frame of an image of the live video, sets a plurality of advertisement labels for the any frame of the image, associates the advertisement labels with advertisement files, and simultaneously monitors frequencies of occurrence of the advertisement labels. By reasonably setting an advertisement playing threshold A, while a user watches the video, the advertisements having relatively large association with the video are guaranteed to be played; furthermore, the problem of the frequent advertisements due to a fact that the frequencies of occurrence of the advertisement labels are relatively large is avoided and the aversion of the user to the advertisements because the advertisements occur frequently is reduced; and meanwhile, according to the frequencies of occurrence of the advertisements, flexible adjustment is performed on the A, thereby preventing the same advertisement from occurring for many times; and the different advertisement labels are individually recorded, and are played once when a certain threshold is reached, and an advertisement playing sequence can be scattered, so the problems that many advertisements need to be played at a same time slot and are arranged difficultly are solved.