Saline　wastewater　present　in　municipal　pipe　networks　poses　challenges　to　biological　nitrogen　removal　due　to　its　inhibition　on　microorganisms.　This　study　focuses　on　the　effects　of　low　salinity　(0.0%,　0.4%,　0.7%　and　1.0%)　on　a　system　featuring　a　combination　of　nitritation/anammox　in　oxic　stage　and　denitratation/anammox　in　anoxic　stage　(double-anammox)　in　a　step-feed　SBR　for　municipal　wastewater　over　a　period　of　130　days.　The　results　showed　that　a　maximum　nitrogen　removal　efficiency　of　81.2%　was　achieved　at　a　salinity　of　1.0%　with　anammox　contribution　of　76.5%.　Analysis　of　anammox　contribution　and　sludge　activities　discovered　that　low　salinity　promoted　both　nitritation　and　denitratation,　further　enhancing　the　coupling　with　anammox.　Further,　microbial　analysis　confirmed　that　Ca.　Brocadia　was　enriched　on　biofilms　from　0.21%　to　0.51%　and　Nitrosomonas　was　enriched　in　flocs　from　0.50%　to　1.04%.　Overall,　the　double-anammox　process　appears　to　be　a　promising　method　for　the　treatment　of　saline　wastewater.