Abstract: Welding properties of submarine steel and welding consumables of Japan were presented in this paper.The plentiful test results of NS63 and NS80 steel indicate that the dissimilar preheating and interpass temperature is choose to avoid welding crack according to the different steel strength grade、plate thickness and the different restraint stress.The temperature generally varies between 50℃ to 150℃,the relevant heat input shall be such matched from 16kJ/cm to 24kJ/cm and critical cooling speed fits with welding consumables that to satisfy the mechanical properties requirement of weld metal.Furthermore,the vapor pressure in working environment should be restricted(≤25mmHg) and the moisture absorption quantity of the welding consumables shall be less than 0.20%.A mass of low-strength matching welded joints tests indicates that the welded joints still possess favorable integrated property when the strength of weld metal is 15% lower than that of base metal suggesting that the low-strength matching welded joint is reliable for application in submarine.