Located in the north of China,Otindag sand field is an important source of dust which influences regional or even hemispheric climate change.However,the formation age and the landform process history remain incompletely understood,just as which was formed as far as in the Later Tertiary at least according to the red sand layers,underlying red clay and sandy bedrock.Our new OSL dating and sediment sequence indicates that shifting sand dunes prevailed in Otindag sand field by at least 25 ka years ago.During 25-11 ka,white aeolian sand was widespread overlying the lacustrine (or alluvial) sediment even bedrock of hillside,which was the foundation,throughout of the sand field.This result implicates that Otindag sand field probably formed at least 25 ka which is different from previous viewpoint.We attribute this event to the Last Glacial Maximum climatic deterioration responding to changes in the Asian monsoon coupled with the ice volume shift in north hemisphere.