The invention discloses a method for detecting data collection omission in a traffic collection device and relates to an information security technology in the technical field of information. The method comprises the following steps: step 1 is discovery of omission of active IP data, and step 2 is discovery of omission of active domain name data. According to the invention, a DNS data source is used to supplement original data, and data which has the attribute of a computer room is extracted, and then a simulation request is performed, such that the performance demand for the simulation request is reduced, a more comprehensive simulation request is also provided, and discovered omission is more comprehensive and accurate. When the simulation request is performed, an http (get/post) requestis firstly performed, and then afterwards, data whose simulation request result return values are not within a reasonable scope is subjected to an https (get/post) request. Such a mode, compared to amode of performing http&https simulation requests on all data, can reduce the performance demand for the simulation request, and compared to a mode of only performing the http simulation request, canalso enhance comprehensiveness of the simulation request. According to the invention, the network supervision level can be effectively improved, and data missed by an information security managementsystem is discovered for analysis of omission reasons of the information security management system.