Adult-onset Still's disease (AOSD) is a rare inflammatory disorder involving multiple systems. It can present a wide range of symptoms like maculopapular rash, fever, and arthralgia, which may overlap with many other disorders, making it difficult to diagnose. Unknown etiology and no diagnostic tests further make it complex to establish the diagnosis of AOSD. We report the case of a 30-year-old female who presented with persistent rash, joint pain, and fever, along with positive antinuclear antibodies (ANA), diagnosed with this condition. The patient improved with corticosteroids and the plan is to start disease-modifying antirheumatic drugs (DMARDs) after tapering off steroids.