Fatigue is commonly reported by patients with noncancer gastrointestinal (GI) disorders such as organic and functional GI disorders. This critical review was conducted to evaluate fatigue measures that have been used in these patients. A systematic search using six databases (PubMed, PsycINFO, EMBASE, CINAHL, ProQuest, and Cochrane Review) was conducted from January 2000 to June 2014, and evaluations and reviews of fatigue instruments were performed by two independent reviewers (author and medical librarian). Fourteen instruments from 25 studies were identified. Ten instruments were solely focused on fatigue and four were multisymptom instruments. The average quality score of the 14 instruments was 10.7 (range, 6-14) out of 14. There were five instruments with high overall scores based on usability/feasibility, clinical/research utility, and psychometric properties (3 fatigue-specific and 2 multisymptom). There are valid and reliable measures that are currently available to assess fatigue in noncancer GI patients. Utilization of these common measures may assist clinicians (GI healthcare providers) and researchers to better understand the impact of fatigue in these patients. The instruments with low-quality scores cannot be chosen for routine use without further validation.