The observation of earthquake,deformation and volcanic gas geochemistry show that Changbaishan volcano experienced an unrest from 2002 to 2005. Before and after the volcanic unrest,station CBS recorded continuous and stable broadband seismic data. According to the previous observation results,the main type of volcanic earthquake during the Changbaishan volcanic unrest is volcanic tectonic earthquake,accompanied by a small number of harmonic earthquakes. In this paper,based on the matched-filter technique,the three component seismic data before and after the volcanic unrest from 1999 to 2007 from Changbaishan Volcano Observatory were scanned by template,and 3763 clear volcanic seismic events were obtained,including 125 harmonic spectra(HS)events,3618 volcanic tectonic(VT)events,and 20 long-period(LP)events. The volcanic earthquake events during the volcanic unrest can be divided into three types:volcanic tectonic events,long-period events and harmonic spectra events. A model of "energy transfer between deep earthquakes and volcanoes" is proposed for Changbaishan volcanic unrest mechanism from 2002 to 2005 as follows. First,Wang Qing deep-focus earthquake energy release and transfer,causing the lithospheric stress state fluctuation in Changbaishan volcanic area. Then,after the mantle magma chamber is disturbed by stress,the magma channel opens and a small amount of magma intrudes into the crust magma chamber. Finally,mixed degassing of magma leads to the pressure rise of magma chamber in the crust,which leads to the micro fracture of the top rock,resulting in volcanic tectonic earthquake. When gas and fluid fill these fissures,LP and HS type volcanic earthquake events occur.