Abstract: The successive main ion profiles of the snowpit samples collected from No.1 Glacier at the head of the Urumqi River during the early ablation period of 1996 were compared to investigate the factors that affect the re-location of the ionic species within the glacier snowpacks. It is found that most of the main ions preserved in the snowpacks since the precious melt season had percolated downwards, then were stopped at the snow/ice boundary or in the super-imposed ice layer, where layers with significantly high ionic concentrations were observed. When heavy melting happened, most of the ions might be released from the snowpacks with the glacier runoff, consequently the glacier ice with extremely low ion concentrations would form. Thus it is suggested that the ion elution processes might deteriorate the quality of ice core chemical records for paleoenvironment reconstruction. In addition, preferential elution was observed among the main ions, and the leaching degree varied significantly for different ions at different leaching stages.