An interlocking chain type forward and backward actuating device (100, 200, 300) comprising a pair of interlocking chains (110, 310), a driven body (120, 320), and a chain guide plate (130, 230, 330), wherein the interlocking chains (110, 310) includes hook-shaped inner tooth plates (111, 211, 311, 311A, 311B) and hook-shaped outer tooth plates (112, 212, 312, 312A, 312B), the hook-shaped outer tooth plates (112, 212, 312, 312A, 312B) are arranged alternately with the inner tooth plates (111, 211, 311, 311A, 311B) in a chain longitudinal direction, a large number of the inner tooth plates (111, 211, 311, 311A, 311B) and the outer tooth plates (112, 212, 312, 312A, 312B) are coupled to one another in the chain longitudinal direction with coupling pins (113, 113A, 113B, 213A, 213B, 313, 313A, 313B), the coupling pins (113, 113A, 113B, 213A, 213B, 313, 313A, 313B) extend through the inner tooth plates (111, 211, 311, 311A, 311B) and the outer tooth plates (112, 212, 312, 312A, 312B) in a chain width direction, the pair of interlocking chains (110, 310) is driven by a drive sprocket (SP1, SP3) such that the interlocking chains (110, 310) become rigid with inner tooth plates (111, 211, 311, 311A, 311B) of one interlocking chain (110, 310) be interlocked with inner tooth plates (111, 211, 311, 311A, 311B) of other interlocking chain (110, 310), and outer tooth plates (112, 212, 312, 312A, 312B) of the one interlocking chain be (110, 310) interlocked with outer tooth plates (112, 212, 312, 312A, 312B) of the other interlocking chain (110, 310), and such that the interlocking chains (110, 310) bifurcate from each other with the interlocked inner tooth plates (111, 211, 311, 311A, 311B) being disengaged and the interlocked outer tooth plates (112, 212, 312, 312A, 312B) being disengaged; the driven body (120, 320) is mounted to the pair of interlocking chains (110, 310), the driven body (120, 320) is moved forward and backward according to forward and backward movement of the pair of interlocking chains (110, 310), the interlocking chain type forward and backward actuating device (100, 200, 300) comprising a chain guide plate (130, 230, 330) and a chain locus regulating means, wherein the chain guide plate (130, 230, 330) includes a disengagement part guide (131A, 231A, 331A), the disengagement part guide (131A, 231A, 331A) guides a projecting portion of the coupling pin (113, 113A, 113B, 213A, 213B, 313, 313A, 313B) in the chain width direction at a chain disengagement part (110A, 210A, 310A) where the interlocking chains (110, 310) are disengaged from each other, the chain guide plate (130, 230, 330) is arranged respectively at both sides of the pair of interlocking chains (110, 310) in the chain width direction, the chain locus regulating means guides a rigid chain part (110B, 210B, 310B), the chain locus regulating means includes a chain locus regulating face (S1, S2, S3), the chain locus regulating face (S1, S2, S3) slidably contacts the rigid chain part (110B, 210B, 310B) where the interlocking chains (110, 310) are interlocked with each other to become rigid, the rigid chain part (110B, 210B) includes one of said coupling pins (113, 113A, 113B, 213A, 213B), the coupling pin (113, 113A, 113B, 213A, 213B) extending through a coupling pin passage (131B, 231B) in a rigid chain direction, the coupling pin passage (131B, 231B) is formed at the chain guide plate (130, 230) with the coupling pin passage (131B, 231B) communicating with the guide for the chain disengagement part (131A, 231A), the coupling pin passage (131B, 231B) has a passage width larger than a guide width of the disengagement part guide (131A, 231A), and guiding the interlocking chains (110, 310) with the disengagement part guide (131A, 231A, 331A) is switched to guiding the interlocking chains (110, 310) with the chain locus regulating face (S1, S2) at a chain disengagement position.