The invention discloses a method and system for compressing and reconstructing data of a wireless sensor network based on symbolic aggregate approximation. The method comprises the following steps of: S1, obtaining a time sequence formed by the monitoring data in a data sliding window acquired by various nodes of the wireless sensor network, and standardizing the sequence to obtain a standardized sequence; S2, reducing the dimensionality of the obtained standardized sequence, and signifying the mean value of various time sequence sub-segments to obtain a SAX symbol sequence; S3, judging whether single node inhibits the SAX symbol sequence sending process in the present time through the time correlativity or not, and inhibiting sending of redundant information through the spatial correlativity among different nodes; and S4, recovering data, which is not transmitted by the nodes, when various nodes in one period complete the spatial correlativity inhibiting process and the receiving end finishes acquisition of current data. By means of the invention, the energy and the communication bandwidth of the wireless sensor network can be greatly saved; and the work life period of the wireless sensor network, the power of which is supplied through a battery, is prolonged.