Presented at the 2013 Aquarius/SAC-D Science Team MeetingA validation campaign was carried out to evaluate the SMOS-MIRAS Soil Moisture (SM) SML2UDP product (v5.51) in the Pampean Region of Argentina. The study area was selected because it is a vast area of flatlands containing quite homogeneous rainfed croplands considered SMOS nominal land uses. Transects of ground SM measurements were collected by ThetaProbe ML2x probes within four ISEA-grid SMOS nodes, where permanent SM stations are located. The first validation results showed a negative bias between concurrent SMOS data and ground SM measurements, which means a slight SMOS-MIRAS underestimation, and a standard deviation of ±0.06 m3m−3. Additionally, a correlation was obtained between the ground SM values and the SM station data within a node. Therefore, the station data adjusted to obtain node representative values could be used to continue the validation of SMOS-retrieved data in the future.