The paleoclimate of the Chungbu Mountainous Region, Mts. Seorak and Sobaek, was estimated by means of dendroclimatic methodology, The annual growth value of tree-rings is deeply interrelated with the mean temperature of April-May and July-August. The mean temperature of April-May of the reconstruction period(1635-1911), observation period(1912-1989), and the whole period(1635-1989) is 13.58$^{circ}C$, 13.69$^{circ}C$, and 13.6$0^{circ}C$, respectively. That of July-August is $24.50^{circ}C$, $24.62^{circ}C$, and $24.58^{circ}C$ respectively. The reconstructed mean temperature data for April-May and for July-August reveal 13.2 and 12.9 year cycles.