AbstrakPenambatan nitrogen oleh bakteri rhizosfer dapat dimanfaatkan untuk menyiasati dampak salinitas pada tanah sawah pesisir. Kemampuan tersebut disebabkan oleh aktivitas nitrogenase yang disandikan gen nifH pada komponen II. Penelitian  ini bertujuan  menganalisis aktivitas nitrogenase pada kondisi salin dan mengidentifikasi gen nifH. Sebanyak 50 isolat bakteri rhizosfer asal tanah sawah pesisir daerah Eretan dan Patimban, Jawa Barat telah dianalisis. Lima isolat yang menunjukkan aktivitas nitrogenase pada kondisi salin adalah Er B1 3, Er B1 4, Er B1 9, Er B2 10, dan Ptb B1 4. Gen nifH kelima sampel diidentifikasi menggunakan PCR menghasilkan amplikon berukuran ~360 bp. Aktivitas nitrogenase tertinggi berdasarkan Analisis Reduksi Asetilen (ARA) diperoleh pada isolat Er B2 10 yang memiliki kekerabatan terdekat dengan bakteri Providencia sp. Hasil yang diperoleh membuktikan bahwa beberapa bakteri asal sawah pesisir dapat menambat nitrogen pada kondisi salin.AbstractThe ability of nitrogen fixation by rhizosphere bacteria could be used to decrease salinity impact in coastal paddy field, due to nitrogenase capability, encoded by a nifH gene in component II. The objectives of this research are to analyze nitrogenase activity in saline condition and identify the presense of the nifH gene. A total of 50 isolates of the rhizosphere bacteria coastal from wetland areas of Eretan and Patimban, West Java, has been isolated and being analyzed. Among them, five isolates i.e. Er B1 3, ER B1 4, Er B1 9, Er B2 10 and Ptb B1 4, showed the nitrogenase activity under saline condition. The polymerase chain reaction (PCR) of the nifH gene from those five samples resulted in the amplicon size of  ~360 bp. The highest activity of nitrogenase assessed by acetylene reduction assay (ARA) was shown by Er B2 10 which closely related to bacteria of Providencia sp. The obtained result showed that several bacteria from coastal paddy field were able to conduct nitrogen fixation under saline stress.