Abstract: Based on an AGDTSM model, this paper decomposes China’s treasury bond rates into interest rate expectation and risk premiums; then from the double perspectives of the expectation channel and the premium channel, it makes an empirical test on the influencing mechanism of monetary policy on the term structure of interest rate of national debt. The findings show that: Firstly, China’s present monetary policy is affecting the term structure of interest rate of national debt mainly through the expectation channel, while the effect of the premium channel is limited. Secondly, the guiding direction of the expectation channel is consistent with the target of monetary policy; the premium channel will weaken the guidance effect of the expectation channel at the initial stage of the policy. Thirdly, the expectation channel has a relatively stronger guiding strength on the short end of the treasury bond yield curve, but weaker on the long end. This difference is the fundamental cause leading to the recent“extreme planarization”of the recent treasury bond yield curve.

Key words: monetary policy; term structure of interest rate of national debt; expectation channel; premium channel