Because of the current inconsistencies in the association between body mass index (BMI) and psoriasis severity, this study aimed to determine aforementioned association. This analytical observational study was conducted in a private hospital in West Java between August and December 2023 using data from medical records of 108 psoriasis cases recruited by simple random sampling. Data were collected on demographic characteristics (age, gender), BMI, and psoriasis severity. BMI was divided into categories following the WHO Asia Pacific region classification. Psoriasis severity was categorized as mild, moderate, and severe, and determined by means of Psoriasis Area and Severity Index (PASI) scores. Data were analyzed by independent t test and Chi-squared tests. Mean age (± SD) of psoriasis subjects was 40.1 ±12.4 years, the most frequent gender was female with 73 (67.6%) subjects, and mean BMI was 25.2 ± 3.3 kg/m2. Fifty-six (51.9%) subjects were obese according to BMI, 24 (22.2%) subjects were overweight, and 28 (25.9%) subjects were of normal weight. A total of 47 (43.5%) subjects had severe psoriasis, followed by moderate psoriasis in 36 (33.3%) subjects, and mild psoriasis in 25 (23.1%) subjects. There was no significant correlation of BMI with psoriasis severity in subjects of productive age (p = 0.249). Healthy lifestyle and weight control are necessary in the management strategy of persons with psoriasis, because of the high prevalence of persons with psoriasis and obesity.