PURPOSE: To place the outlet port of a ladle of a molten metal supply device in the atmosphere of fine particles of carbon thereby to prevent generation and adherence of an oxide.

CONSTITUTION: A burner 5 is fitted to the lower part of each of outlet ports 2 on the outer surface of a ladle main body 1. The burner 5 is positioned in such a manner that it does not contact a molten metal 3' flowing out of the outlet port 2. Flame is arranged to be directed toward the outlet port 2. The burner is provided in each of the outlet ports 2, air is subjected to incomplete combustion without actively supplying to the burner to discharge the flame out of the outlet port 2 thereby to produce the atmosphere to carbon fine particles. Eaves 6 are provided from the upper part of the ladle 1 to cover the outlet ports 2 thereby to make an atmosphere of carbon fine particles of high concentration.