The invention discloses a time-consuming deviation detection method of business expansion process based on a normal distribution model, belonging to the technical field of electric power detection, comprising the steps of analyzing the efficiency of the business expansion process; 2, obtaining factors associate with that time consumption of the business expansion process, and analyzing the factorsassociate with the time consumption of the business expansion; 3, further analyzing the time-consuming distribution of small links of each industry expansion link, and establishing a time-consuming deviation detection and analysis model of the industry expansion link; 4, tracking the long time-consuming work order in real time during the whole process of business expansion and increase speed andefficiency, and then analyzing the causes of the long time-consuming work order. The invention realizes the time-consuming deviation detection and early warning analysis of the business expansion linkby utilizing the data analysis means and analyzing the business expansion process service data and the activity record of the business expansion and speed increase management improvement, which is helpful for tracking the progress, finding the problem and analyzing the reason in the whole process of the business expansion and speed increase. The invention also discloses a method for detecting thetime-consuming deviation of the business expansion link.