Operating room of a hospital is a place to do both elective and acute surgery. Operating room condition is associated with the risk of disease transmission such as infections. Nosocomial infections are infections that arise in a period of more than 48 hours after being treated in hospital. This research aims to determine the pattern of aerobic bacteria that could potentially cause nosocomial infections in Operating Room of RSAD. Robert Wolter Mongisidi Manado. This research uses descriptive prospective study where samples were taken by acquiring swabs from the walls, floor, bed and also air sample as much as 25 samples. This research found 6 species of bacteria, 3 Gram positive bacterias and 3 Gram negative bacterias. Gram-positive bacteria consisting of Staphylococcus sp (40.3%), Streptococcus sp (3.5%) and Bacillus sp (35.08%), whereas Gram-negative bacteria consisting of Enterobacter agglomerans (5.3%), Proteus sp (12.3 %) and Neisseria sp (3.5%). The most bacteria that could potentially cause nosocomial infections were Staphylococcus sp (40.3%).Keywords: nosocomial infection, operating room, aerobic bacteria. Abstrak: Kamar operasi suatu rumah sakit merupakan tempat untuk melakukan tindakan pembedahan baik secara elektif maupun cito. Kondisi kamar operasi berhubungan dengan resiko penularan penyakit salah satunya melalui infeksi. Infeksi nosokomial adalah infeksi yang timbul dalam kurun waktu lebih dari 48 jam setelah dirawat di rumah sakit. Penelitian ini bertujuan untuk mengetahui pola bakteri aerob yang berpotensi menyebabkan infeksi nosokomial di kamar operasi CITO RSAD Robert Wolter Mongisidi Manado. Penelitian ini menggunakan metode penelitian deskriptif dengan pendekatan prospektif dimana sampel diambil melalui usapan pada dinding, lantai, dan tempat tidur serta pengambilan sampel udara sebanyak 25 sampel. Hasil penelitian ditemukan 6 jenis bakteri, 3 bakteri Gram positif dan 3 bakteri Gram negatif. Bakteri Gram positif terdiri dari Staphylococcus sp (40.3%), Streptococcus sp (3.5%) dan Bacillus sp (35.08%), sedangkan bakteri Gram negatif yaitu Enterobacter agglomerans (5.3%), Proteus sp (12.3%) dan Neisseria sp (3.5%). Bakteri yang berpotensi menyebabkan infeksi nosokomial terbanyak yang ditemukan adalah Staphylococcus sp (40.3%). Kata kunci: infeksi nosokomial, kamar operasi, bakteri aerob.