The invention discloses continuous production equipment for a thermal insulation layer of a plastic thermal insulation pipeline. The continuous production equipment comprises a foaming machine and a thermal insulation layer molding device, wherein the thermal insulation layer molding device comprises a rack; two conveyer belt mechanisms are arranged on the rack; each conveyor belt mechanism comprises belt pulleys and a conveyer belt mounted on the belt pulleys in a sleeving manner; two adjacent belt pulleys are working belt pulleys of which a central connection line is parallel to the feed direction of a working inner pipe; thermal insulation layer molding mold units are mounted on the conveying belt; semicircular grooves are formed in the end faces of one ends, back to the conveying belts, of the thermal insulation layer molding mold units; the thermal insulation layer molding mold units which are respectively arranged on the two conveyer belts and are located between the two corresponding working belt pulleys are matched with each other and are spliced through the semicircular grooves to form a round-tube-shaped thermal insulation layer molding channel for allowing the working inner pipe to pass through; the geometric dimension of the thermal insulation layer molding channel is larger than that of the inner working pipe; and a foaming material output port of the foaming machine is in the thermal insulation layer molding channel. The invention further discloses a continuous production method for the thermal insulation layer of the plastic thermal insulation pipeline.