The weldability and joint performance were evaluated for newly developed 60kg/mm$^$2/ steel which had low cold cracking susceptibility. The main results obtained were as follows; In case of quenched and tempered 60kg/mm$^$2/ steels, it was very effective to improve weldability and joint performance by lowering carbon and Pcm level. Very small addition of about 0.001 to 0.002wt% boron exhibited an appreciable compensation effect on strength which was decreased by lowering carbon and Pcm level. As a result, the newly developed steel was able to be welded without preheating and exhibited superior joint performance to conventional steels.