The invention discloses an incremental crawling method for website information. The method comprises the steps of crawling data with set length according to a website information presentation sequence; including into a data array according to the website data presentation sequence, wherein a comparison window is arranged at the tail end of the data array; detecting the repeatability rate of data in the comparison window and the crawled data; stopping crawling data when the repeatability rate reaches the preset value, and otherwise, repeating the processes above until the repeatability rate of the data in the comparison window and the crawled data reaches the preset value, and then stopping crawling data. According to the method, the crawling consumption is decreased under allowable crawling leakage rate if the increment crawling is not performed for the website information strictly according to the time sequence; when in the working process, the set length of data crawling and the length of the data array can be dynamically adjusted, so that the algorithm working efficiency can be increased, and different demands on crawling leakage and crawling loss can be met.