Procambarus clarkii is one of the important economic species in China and has been served as tasty food in recent years after being introduced to Nanjing. Significant problems of environment factors, such as salinity, pH and temperature, especially salinity, has the potential to result in significant economic losses in many crayfish-producing farms in China. miRNAs are a kind of ~ 22 nucleotide small non coding RNAs which were encoded by plants, animals and some viruses with functions in RNA silencing or post-transcription regulation. We constructed four sRNA library of P. clarkia from different tissues and treatments by using high-throughput sequencing technology. A total of 101 conserved miRNAs and two novel pre-miRNAs were identified and RT-qPCR were further performed to confirm existence of part of identified miRNAs. A genome wide expression profile of salt-tolerance miRNAs was proved and three miRNAs were further validated by RT-qPCR with dynamic response to different salinity stages. The study of miRNAs in P. clarkia can help us better understanding the role of miRNAs in salt-tolerance in P. clarkia.