Abstract: The chemical composition of pollen of Populus euphratica and P.pruinosa and vigour change of pollen stored in room temperature and 4℃ condition were comparative studies.The results showed that the time of retention vigour of pollen of P.pruinosa in two storage conditions was longer than that of P.euphratica.When pollen of the same species were stored for same time,the vigour of pollen stored in 4℃ condition was stronger than that stored in room temperature.The moisture,starch content of pollen of P.pruinosa was higher than that of P.euphratica,but the content of protein,reducing sugar and 17 kinds of free amino acid were lower than that of P.euphratica.