The plant miRNA microarray V2.0 is based on 994 sequences in miRBase 9.1 (Feberary 2007) of Sanger Database. 348 unique miRNAs were retained after removing the redundant sequences. Coupled with 4 miRNAs predicted by Zhu Jian-Kang on Cell Journal, and 74 miRNAs predicted by Chen Fan (CAS), there are 426 miRNAs probes in all on the array. These probes were spotted on a piece of 75mm multiply 25mm, chemical modified glass using SmartArrayTM (CapitalBio Corp., Beijing, China ) machine. Eight manufactered RNA with 30nt in length were used as exogenous controls (Zip5, Zip13, Zip15, Zip21, Zip23, Zip25, Y2, Y3). Hex was used as positive control and 50% DMSO was negetive control. The whole array was divided as 4 subarray. There are 18 rows and 21 columns in each subarray. The diameter of spots was 150 micrometer with 225 micrometer intervals between two spots. Each probe was spotted in three technical replicants.