Abstract: Objective To compare the expression profiles of microRNAs (miRNAs) between rectal adenocarcinoma and normal rectal mucosal tissues, further to identify the differentially expressed miRNA possibly associated with the development of rectal cancer. Methods miRNA expression profi les of three rectal adenocarcinoma samples and related normal rectal mucosal tissues were performed by miRNA microarray analysis. Real-time quantitative RT-PCR was performed to confirm the expressions of hsamiR-187* and hsa-miR-224 in another 15 cases of rectal adenocarcinoma. Results A total of 70 miRNAs were found to be differentially expressed in rectal adenocarcinoma and normal tissues, including 33 upregulated miRNAs and 37 down-regulated miRNAs. Compared with normal rectal samples, hsa-miR-187* expression was down-regulated in rectal adenocarcinoma(P<0.001), while hsa-miR-224 expression was upregulated (P<0.001). Conclusion Compared with that in normal rectal mucosal tissues, the specifi c miRNA expression profi le might play an important role in the development of rectal adenocarcinoma.