Background: Approximately 1.4 million patients in the world get infections while being hospitalized, which 10% of them occur in developing countries like Indonesia. The incidence of hospital acquired infection (HAI) in intensive care unit (ICU) reached 51%, which means 2 to 5 times higher than other rooms in the hospital. Comorbidity is one of many factors that can increase the risk of HAI that can aggravate the patient's condition, complicate the handling of the patient's illness, and raise the cost of the hospital. Objective: This study aims to determine the relationship between comorbidity and hospital acquired infection (HAI) on patients in intensive care unit (ICU) at Siloam Hospital Lippo Village. Methods: This study is an observational study with retrospective cross-sectional design. Subjects are 67 patients who had been admitted to intensive care unit (ICU) Siloam Hospital Lippo Village for ≥ 48 hours. Secondary data collection is done by recording, tabulating, and analyzing data obtained from intensive care unit (ICU) Siloam Hospital Lippo Village’s patient database. Result: There are 261 sample which 94 patients had hospital-acquired infection and 167 of them didn’t have it. Generally, there is a significant correlation between comorbidity and hospital-acquired infection (HAI) (p: 0.017), also cerebrovascular disease (p: 0.013) and neurosurgery (p: 0.012) specifically. Conclusion: There is a relationship between comorbidity and hospital acquired infection (HAI) on patients in intensive care unit (ICU) / Latar Belakang: Sekitar 1,4 juta pasien di dunia mendapatkan infeksi saat sedang dirawat di rumah sakit, dimana 10% dari angka tersebut terjadi di negara berkembang seperti Indonesia. Kejadian hospital acquired infection (HAI) di intensive care unit (ICU) mencapai 51% yang berarti 2 sampai 5 kali lebih tinggi dibandingkan ruangan lain di rumah sakit. Komorbiditas merupakan salah satu faktor yang dapat meningkatkan resiko terjadinya HAI yang dapat memperparah keadaan pasien, mempersulit penanganan penyakit pasien, dan meningkatkan biaya rumah sakit. Tujuan Penelitian: Penelitian ini bertujuan untuk mengetahui hubungan komorbiditas dengan kejadian HAI pada pasien ICU di Rumah Sakit Siloam Lippo Village. Metode Penelitian: Penelitian ini menggunakan studi observasi dengan desain retrospective cross-sectional. Subjek penelitian berjumlah 67 pasien yang telah dirawat di ICU Rumah Sakit Siloam Lippo Village selama ≥ 48 jam. Pengambilan data sekunder berupa pencatatan, tabulasi, dan analisa data yang didapatkan dari database pasien ICU Rumah Sakit Siloam Lippo Village. Hasil: Terdapat 261 jumlah sampel pasien dimana sebanyak 94 pasien mengalami HAI dan 167 lainnya tidak mengalami HAI. Secara umum komorbiditas berpengaruh signifikan terhadap HAI (p: 0.017), begitu pula komorbiditas penyakit serebrovaskular (p: 0.013) dan bedah saraf (p: 0.012) secara spesifik. Kesimpulan: hubungan antara komorbiditas dengan kejadian hospital-acquired infection (HAI) pada pasien intensive care unit (ICU). Komorbiditas signifikan terhadap HAI adalah penyakit serebrovaskular dan bedah saraf.