Abstract: There are two limitations in the existing WSN data aggregation methods for preserving data privacy:the communication cost is considerably high and the verification of data integrity is still undesirable. To solve these problems, an elliptic-curve and Hilbert-curve based data privacy-preserving algorithm (ECHCPA) is proposed for data caggregation, especially between cluster heads. The sensed data are encrypted using an elliptic curve and Hilbert curve. In this way, the volume of data transmission is reduced so that the space complexity and communication cost can be lowered. To verify data integrity, the aggregation of the encrypted data is processed at both the parent nodes and testing nodes, and it can be tested by comparing the two aggregated results. Simulations show that compared with iHDA and SMART, ECHCPA performs better in lowering communication costs, with good data integrity and data accuracy.