Taking the microbial communities in the Shapotou deserted area of Ningxia Hui Autonomous Region as a research object,function diversity of microbial communities from fixed dunes crust（J1）,sub fixeddunes crust（J2）,semi-mobile dunes（L1）and sub semi-mobile dunes（L2）were studied using Biolog method.Results showed that physiological action of J1microbial community was the highest,followed by J2,L2andL1in turn.J1,J2,L1and L2had the same performance in utilization of carboxylic acids,polymers and aminoacid,but were different in utilization of sugar,amine/ammonia and parent compounds.The characteristicvalue contributions of PC1,PC2and PC3were 70.16%,19.23%and 10.61%,respectively.It can be concluded that（1）microbial community activity in fixed desert was significantly higher than that in mobile desert;（2）the differences of microbial community structure may result in the utilization of six types of carbonsources in different ways;（3）by principal component analysis,the utilization of acid,sugar and amino acidby desert microbial community was highest and carbon sources utilized were as many as 22types.