PURPOSE: To provide a twin roll type continuous casting method and apparatus, by which a thin cast slab having a prescribed cross sectional shape can be formed.

CONSTITUTION: In this twin roll type continuous casting apparatus, closed frames 8a, 8b, 8c, 8d for separating molten metal surface part in the vicinity of both parts of cooling rolls 1a, 1b from the molten metal surface in the vicinity of the other cooling rolls 1a, 1b are arranged. Gas medium having larger thermal conductivity than gas medium existing on the molten metal surface in the outside of the closed frames 8a, 8b, 8c, 8d, is supplied into the closed frames 8a, 8b, 8c, 8d.