The study on social network marketing effect tracing is still in the infancy. To meet the need of social network marketing effect, a platform is designed for social network information collection and data processing. The platform uses crawler technology to obtain information. Although the speed of information collection is limited, the platform can acquire as much information as possible. The spread diagram for social network marketing tracking will be obtained by building a forwarding tree algorithm. Experiment results show that the platform can automatically acquire and process the data, and then draw an information dissemination graph. The information dissemination graph is used to find the tipping point and comment information in the information dissemination, that is, the important relationship nodes and feedback information in relationship marketing. The platform can also obtain other related statistics information of interactive users to facilitate the tracking of social network marketing effect.