Although the Sheehan Disability Scale (SDS) is one of the most extensively used and tested disability measurements, there has only been one psychometric evaluation of its properties in a Chinese-speaking population. Here, we provide a comprehensive psychometric assessment of the scale in 465 Mandarin-speakers who were accessing information online regarding psychotherapy. Principal component analysis and subsequent confirmatory factor analysis indicated that the SDS is one-dimensional (normed fit index = 0.976, non-normed fit index = 0.97, comparative fit index = 0.98, goodness-of-fit index = 0.967, standardized root mean-square residual = 0.023, root mean-square error of approximation = 0.149). The SDS exhibited excellent internal consistency (α = .89) and moderate test–retest reliability when readministered approximately 8 days later (intraclass correlation coefficient = 0.55). Convergent validity was demonstrated by strong relationships with other measures of functional impairment (FI), while divergent validity was evidenced by fair correlation with a treatment ambivalence measure. Known-groups validity analyses showed that high FI was associated with significantly higher clinical scores of anxiety, depression, and obsessive-compulsive symptoms. Regression analysis indicated that the Depression Anxiety Stress Scale-21 score accounted for 37.6% of variance in FI. Overall, these findings support the reliability and validity of the SDS when used in Chinese treatment-seeking individuals, as well its usefulness as an online screening tool of FI.