In order to improve the shortcomings of large hardware volume, large data measurement error, weak applicability of de-noising algorithm in the current telemetry data detection system. The paper realize the software design of telemetry monitoring system based on the improved wavelet threshold de-noising algorithm for telemetry parameters. In order to confirm the algorithm’s effectiveness, there are many de-noising experiments for telemetry data of airspeed and engine speed based on improved wavelet threshold algorithm. It shows that the algorithm’s de-noising effect for telemetry airspeed data is significantly improved, the square sum of measurement errors is reduced to 2199.6 and the similarity between the de-noising fitting curve and the original data curve is as high as 0.9889, and it has good generality in data de-noise for other telemetry parameters.