Potential of various techniques that utilize data from multiple sensors for mapping of wetlands on Tibetan Plateau have been evaluated. Optical and thermal infrared bands from Landsat and Corona together with SAR data from TerraSAR-X, ALOS/PALSAR have been used. Closed basin of Nam Co (‘Co’ means lake) (30° N, 90° E) has been selected as the study area. It belongs to the zone of discontinuous permafrost. Time series of Landsat data has been complemented by Corona image from 1965 and used to analyze changes of wetland area. Interpretation of wetlands from Corona image from 1965 features high quality. It was used as reference for comparison with time series of Landsat optical data with support of its thermal infrared band. Pauli decomposition image from ALOS PALSAR clearly has good potential usage in wetland mapping. The wetland area was relatively stable in the study region. Some parts of wetlands have been flooded by the lake transgression since 1965. In order to understand overall trend, more research has to be carried out in terms of scale, both in time and space. Relationship between surface properties of wetlands and underlying permafrost layer has to be better understood by further research.