PURPOSE: To obtain bulky silk yarns having a feeling and texture resembling those of hand spun silk yarns, by entangling several raw silks reeled from mutually separated positions as a core yarn with baves reeled from annular cocoon baths, and integrating both.

CONSTITUTION: Several raw silks (A,A...) are passed through yarn guides 2,2... and collected into a core yarn (B), which is integrated with baves reeled from cocoons (b) in annular cocoon baths 4 and 5, provided around the core yarn (B), and filled with hot water while rotating the cocoons (b) with water streams therein. The yarns are then passed through a yarn guide 3, collected integrally and wound. The resultant yarn in the form of a skein is dipped in hot water to soften sericin, and the yarn is dried under no tension condition to fix the entangled state.