This study was carried out to investigate the solid wood bending properties of red pine(Pinus densiflora S. et Z.)naturally grown in Korea by boiling treatment The specimens were green and their dimension was $15 imes15 imes350mm$. The optimum conditions for solid wood bending processing of pine lumber are shown in Table 6 and the minimum solid bending radius was 240 mm in boiling treatment. The effects of knot on the degradation of bending processing properties were very severe and the failures of diagonal and torn grained wood were 20% and 30% respectively.