An indoor smoking detection alarm method comprises the following steps of detecting whether there is a high-temperature suspicious area in an indoor space, wherein a temperature of the high-temperature suspicious area is at least 200 DEG C; through an image acquisition device, acquiring all the indoor images and using a threshold segmentation method to segment a suspicious area from the images; detecting an area of the suspicious area, carrying out characteristic matching on the area of the suspicious area and an area threshold of a cigarette end, and then detecting minimum and maximum boundary points of an abscissa and an ordinate on a boundary point of the suspicious area, and carrying out characteristic matching on the boundary point of the suspicious area and a boundary point when a cigarette burns; detecting whether the suspicious area is in a stationary state or a moving state and determining whether to start an alarm device according to the state of the suspicious area. By using the method in the invention, an indoor smoking behavior can be rapidly discovered; management personnel is prompted to prevent or punish an indoor smoker so that a public order is maintained and benefits of the most people are guaranteed.