This research evaluated the relation and fluctuations in stress and sleep quality in athletes with disabilities (AwD) during the period before and after the 2020 Tokyo Paralympics, amidst the COVID-19 pandemic. Assessments were conducted every 3 months over a period of 10 months, encompassing three distinct pandemic phases. Results showed significant variations in perceived stress (F = 9.41, ηp² = 0.09, p < 0.01) and sleep quality (F = 10.55, ηp² = 0.10, p < 0.001), with initial increased stress and poorer sleep, improving at the midpoint. Sleep quality components varied over time (p < 0.05), except for sleep medication use and daytime dysfunction. Results indicated a direct relationship where poor sleep potentially causes increased stress β = 0.24, p < 0.01; β = 0.13, p < 0.05). The study underscores the need for regular stress assessments and development of sleep routines independent of external circumstances.