Liver cytosol antibody type 1 (anti‐LC1) is reported to be a marker of type 2 autoimmune hepatitis (AIH), a type of autoimmune liver disease (AILD). However, anti‐LC1 is not entirely disease‐specific, and its clinical value in other hepatic diseases has not been well elucidated. Our study aimed to explore the associations between the diagnoses and outcome of decompensated cirrhosis or liver failure (DC/LF) in patients positive for anti‐LC1. A total of 157 patients positive for anti‐LC1 were included in our final analysis. DC/LF was defined as the outcome of patients positive for anti‐LC1. The risk of DC/LF according to diagnosis was estimated using multivariable Cox proportional hazards models, while stratified Cox regression models were used in the subgroup analyses. The diagnoses of patients positive for anti‐LC1 were found to be comprised of various liver disorders. Versus other diagnoses, viral hepatitis was associated with a 2.25‐fold increased risk of DC/LF in these patients, independent of sex, age, disease course, treatment and drinking history. Additionally, the associations were more significant by subgroup analysis in male patients, younger patients, non‐newly diagnosed patients, patients without treatment and patients without drinking history. Anti‐LC1 is not a disease‐specific antibody, as it was found in multiple types of hepatic disease. Furthermore, viral hepatitis rather than AILD was associated with an increased risk of DC/LF in patients positive for anti‐LC1. These findings emphasize the important role of viral hepatitis in the progression of DC/LF in patients positive for anti‐LC1.