Viroids are the non-coding,singlestranded,circular RNAs molecules with sizes range of 246 to 401 nucleotides(nt). They can infect certain plants. Recent findings, however, showthatviroid infection is associated with the appearance of viroid-derived small RNA (vd-sRNA). These vd-sRNAs have sizes similar to endogenous small interfering RNA and microRNA (miRNA) indicating the possibility of connection of vdsRNA to the induced symptoms