The utility model relates to a long-range transmission type sulfur hexafluoride gas density micro-water relay which is applied to sulfur hexafluoride electrical equipment. The long-range transmission type sulfur hexafluoride gas density micro-water relay comprises a housing (8). The outer sides of the housing (8) are respectively fixedly provided with a connection terminal (15) and a joint (9). A base (5) is fixedly arranged inside the housing (8). The relay is characterized by further comprising a Bourdon tube (3). One end of the Bourdon tube (3) is fixed on the base (5) while the other end is connected with one end of a temperature compensating piece (4). The other end of the temperature compensating piece (4) is connected with the input end of a displacement reduction mechanism (7) through a connecting piece. The output end of the displacement reduction mechanism (7) is connected with a pointer (2). A dial (1) is further fixedly arranged on the base (5). The long-range transmission type sulfur hexafluoride gas density micro-water relay provided by the utility model has the characteristics of high precision, good electrical performance of a signal generator and good joint contact. The relay further achieves a long-range density and micro-water content transmission function.