The invention discloses a construction progress monitoring and early warning method and system. The method comprises the steps that the spatial position of a current construction segment in a construction scene is acquired; the real-time construction progress corresponding to the current construction segment is determined according to the corresponding relation between the real-time spatial position and the construction progress; the real-time spatial position is compared with a preset planned spatial position, when the real-time construction progress lags behind the target construction progress, the construction progress is adjusted, an adjusted target construction plan is sent to a constructor, and progress early warning prompt information is sent; the real-time construction progress ismonitored, and related personnel are informed in time when the construction progress lags behind, so that the related personnel can reasonably adjust a construction plan and reasonably allocate construction resources. The defect that the construction progress is not controlled due to the fact that construction adjustment cannot be accurately and effectively conducted in traditional construction isovercome.