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Soil moisture is an essential variable in many hydrological and meteorological models. Spatially continuous soil moisture datasets are important for understanding water cycle and climate change. Currently, satellite-based microwave sensors have been the main resources for obtaining global soil moisture data. This paper evaluates the performance of different soil moisture products from the combined Essential Climate Variable (ECV) and Soil Moisture and Ocean Salinity (SMOS) satellite against the stations within the OzNet soil moisture networks over southeastern Australia. SMOS soil moisture products obtained from two versions (ascending and descending) were included. The evaluations were carried out at both network and site scales. According to the validation results, the ECV products outperformed the SMOS products at both scales. Comparing the two versions of the SMOS products, the SMOS ascending product generally performed better than the SMOS descending product and obtained comparable accuracy to the ECV product at Kyeamba and Yanco sites. However, the SMOS ascending performed poorly at the Adelong sites. Moreover, the ECV product has less data gaps than the SMOS products, because the ECV products were developed by combining passive and active microwave products. Consequently, the results in this study show that the combined ECV product is recommended, as both accuracy and integrity of the soil moisture product are important. The SMOS ascending product is recommended between the two overpass versions of SMOS products.