We used this microarray to monitor rice miRNA expression profile under osmotic stress. Most of rice miRNAs have no significant change. miR-169f showed osmotic-responsive up-regulation. However, the others members of miR-169 family displays no responses to the osmotic stress. Keywords: microRNA,rice,osmotic stress,miR-169 The six selected time points after PEG treatment were 0h, 0.5h, 2h, 6h, 24h and 48h. For each sample, two independent small RNA libraries (biological replications) were generated and two independent reverse transcription/amplifications/hybridizations (technical replications) were performed for each library. Thus, for each sample data was collected from four independent hybridizations.