Sweet potato is an economic food crop which originated from the tropics.During the storage period,the expression of specific genes and the change of physiological indexes induced by low temperature,which seriously affected the quality of sweet potato.In the present study,three independent small RNA libraries from storage roots of sweet potato were constructed and sequenced with the high-throughput Illumina Solexa system,systematic identication and functional analysis of miRNAs under chilling stress were carried out to clarify the molecular mechanism of chilling resistance.