A technique for estimating tropical cyclone (TC) intensity over the Western North Pacific utilizing FY3C Microwave Temperature Sounding (MWTSII) data was developed. First, the limbadjustment was conducted to correct the data of Channels 5-8 to the values they would have in a vertical view, and the corrected deviations were all smaller than the instrument sensitivity. Then the radiance anomaly (core value minus an average environmental value) was used to analyze the characteristics of the TC warm core, and the magnitude and shape feature of the warm core were found related to the TC intensity. As TC intensity gets stronger, the magnitude increases and the shape feature gets clearer and more complete. Finally, an estimation model was estabished using the maximun radiance anomaly of Channel 6 and Channel 7. The standard deviation was 13.0 hPa. After the correction of the bias resulted from the unevenly distribution of MWTSII footprints, the standard deviation was reduced to 12.0 hPa, and, then further reduced to 11.1 hPa after the latitude was taken into account.