PURPOSE: To high efficiently build up the deposited metal containing desired chemical composition, by preparing the strip electrode with material of chemical composition for easy forming work, and by combining this electrode with another strip electrode of dissmilar chemical composition into a composite strip electrode with which the build up welding is carried out.

CONSTITUTION: This is a welding method which can carry out the wide build-up welding by utilizing, even a metal of chemical composition difficult to prepare a wide strip electrode, for forming the deposited metal; hereupon, the melt of metal is utilized for melting the chemical components of individual electrode material together with to form a deposidted metal containing desired chemical composition. For this purpose, the chemical composition of plural electrodes is respectively compounded so as to form a desired deposited metal when they are molten together with. When two kinds of strip electrodes 23 and 24 are employed, the ratio between rotating speeds of feed rolls 21 and 22, that is the ratio between feeding speeds, can be controlled for forming the deposited metal into the desired chemical composition.