Abstract: Abstract: Because the present low-frequency ultrasonic nozzles have such existing disadvantages as follows: high driving voltage，low working efficiency, serious heating of the driving circuit and nozzle，a large volume of low-frequency ultrasonic atomizers, a novel micro index ultrasonic nozzle whose working frequency was 60kHz was designed. According to the frequency equations, the basic sizes of the nozzle were determined. A finite element model of this nozzle was established too. Based on this nozzle's finite element model, a modal analysis, and a harmonious response analysis of this nozzle were conducted. The analysis and calculation results showed that the resonance frequency of the nozzle was 61550Hz and the amplitude of the atomization surface was 8 microns with a 36V driving voltage. Based on ARM9.0, a driving circuit of this nozzle was developed. This nozzle's working frequency as measured by Pvc70A and the atomization surface's amplitude that was generated by 36V driving voltage and measured by CD5-L25 were 59699Hz and 8.63 microns respectively. Compared with this nozzle's working frequency, this nozzle's frequency errors of design and as calculated by FEM were less than 0.5% and 3.0% respectively. The actual amplitude of the atomizing surface of this nozzle was 7.8% less than the harmonic response amplitude calculated by the finite element model. Winner 318B was applied to measure the sizes of the droplets generated by this nozzle driven by 36V and 30V voltage respectively, and the results showed that the voltage had no significant influence on the distribution of the droplets' sizes but on the maxim atomization quantity. Compared with a 28 kHz ultrasonic atomizer, the maxim atomization quantity of the atomizer was nearly identical, but the size and weight were 5.54% and 9.81% of the 28 kHz ultrasonic nozzle's respectively. Droplets generated by this nozzle were finer than those generated by a 28 kHz ultrasonic nozzle.