Harmonic interference signals lead to more and more prominent harmonic current due to the non-linearity of the electrical equipment, appliances, in order to solve this problem, this paper, a low-cost method to suppress harmonic currentand small household appliances vacuum cleaner for the test sample solutions harmonic current. By actual measurement to obtain a large amount of data for the specific data to analyze and summarize excessive harmonic Finally, the use of a passive filter, the test results show that the improved passive filters to select the appropriate parameters for the harmonic current of the vacuum cleaner the inhibitory effect is more apparent.