Summary. Background: Nowadays, large numbers of patients are tested for thrombophilia, even though the benefits of this strategy remain unclear. A potential disadvantage of this predominantly genetic testing is the psychological impact, including fear, depression and worry. Objectives: To systematically review studies that determined the nature and extent of the psychological impact of testing for thrombophilia. Patients/methods: We searched the MEDLINE data base (1966–2008), the EMBASE data base (1985–2008) and the PsychInfo data base (1806–2008) for relevant trials, without language restrictions. Bibliographies of relevant articles were scanned for additional articles. We reviewed all relevant studies that focused on the psychological impact of testing for thrombophilia. Only full papers of studies that included 15 patients or more were considered eligible for this review. Two reviewers independently extracted data and assessed quality. Results: Six studies fulfilled the eligibility criteria. As these studies varied appreciably in methodology, the pooling of data was not possible. Studies of psychological impact of genetic testing for thrombophilia report few negative results, although most assessments were limited to short-term follow-up, or lacked methodological accuracy. Conclusions: No valid conclusions can be drawn about the psychological impact of genetic testing in patients based on the current available literature. Given the large number of patients that are being exposed to testing for thrombophilia, and the uncertain benefits, there is an urgent need for more uniformity in the measurement of the psychological impact of thrombophilia testing.