Joint pain and disease affects more than one in four adults in the United States. We conducted a double-blind, randomized, placebo-controlled trial to investigate the efficacy of a hydrolyzed chicken collagen type II (HCII) supplement in reducing joint-related discomfort such as pain and stiffness, and in improving mobility. We enrolled adults aged 40–65 (65.5% were women) who had joint discomfort, but had no co-morbidities, and who were not taking pain medications. The participants were randomized to receive either the HCII supplement (n = 47) or a placebo (n = 43) for eight weeks. At the baseline, and at week 4 and week 8, we administered the Western Ontario and McMaster Universities Arthritis Index (WOMAC) survey with three additional wrist-related questions and the Visual Analog Scale for assessments of joint-related symptoms. In the WOMAC stiffness and physical activity domains and in the overall WOMAC score, the HCII group had a significant reduction in joint-related discomforts compared with the placebo group. For example, at week 4, the HCII group had a 36.9% reduction in the overall WOMAC score, compared with a 14.3% reduction in the placebo group (p = 0.027). This HCII product is effective in reducing joint pain and stiffness and in improving joint function among otherwise healthy adults.