ZnO nanodots have been grown on Si (100) assisted by anodic aluminium oxide (AAO) template at low temperature (350℃). Regular arrangement to a certain extent in local for ZnO nanodots is observed, and the average diameter of nanodots is about 9. 7nm. Photoluminescence studies at room temperature for photon energy between 2.0 and 3.6 eV reveal a strong single exciton peak at 3.274 eV (378.8 nm) with the green emission fully quenched.Narrow full width at half maximum (FWHM) of the UV emission band (0.14 eV) suggests the as-grown ZnO nanodots have a narrow size distribution.