How to remove the noise cleanly and effectively without losing the property of the raw data in Langmuir Probe (LP) automatic measurement system when measuring the plasma parameters is an important question. And the normal method of data processing such as low-pass filter, moving average data processing can’t solve the question well. In this paper we use two types of wavelet transform to process the LP data step-by-step which are Daubechies Wavelet Transform (DWT) and Biorthogonal Wavelet Transform (BWT), and get quite good results. And in order to prove this, we comparative analyze the results of the actual data processed by several methods above.