The embodiment of the invention provides a method for inquiring about a data flow break point on the basis of a server. In the method, by judging whether at least part of data in a certain window of M windows meets preset conditions or not, the data flow break point is inquired about; when at least part of data in a certain window does not meet the preset conditions, N*U lengths are skipped, and the next potential break point is obtained. The data flow break point inquiry efficiency is improved.