The utility model discloses an isolating-sleeve device for the in-service permanent repairing of a submarine pipeline. The isolating-sleeve device comprises at least one pressure-bearing sleeve and two first connecting sleevelets, wherein the at least one pressure-bearing sleeve is sleeved at the outer part of at least one temporary repairing pipe clamp on the submarine pipeline, the two first connecting sleevelets are sleeved and hermetically connected onto the periphery of the submarine pipeline, and the two first connecting sleevelets are respectively connected to and communicated with both ends of the at least one pressure-bearing sleeve. The isolating-sleeve device is used for in-service permanent repairing of the submarine pipeline; compared with other permanent repairing modes, not only can expenses be saved, but also construction under pressure on the pipeline can be carried out without influencing the normal production of the pipeline, the influence on the integral strength of the pipeline is smaller after the construction is finished, and the isolating-sleeve device has the characteristics of low cost, capability in on-line maintenance, small influence on the submarine pipeline and the like and has good application prospect for the nearshore-segment permanent repairing of long-distance submarine pipelines.