Background: The adoption of open science practices (OSPs) is crucial for promoting transparency and robustness in research. We conducted a systematic review to assess the frequency and trends of OSPs in psychometric studies focusing on measures of suicidal thoughts and behavior. Methods: We analyzed publications from two international databases, examining the use of OSPs such as open access publication, preregistration, provision of open materials, and data sharing. The data were further analyzed based on publication year, first author's region of affiliation, and publication type (open access vs. restricted access). Results: Our findings indicate a lack of adherence to OSPs in psychometric studies of suicide. The majority of manuscripts were published under restricted access, and preregistrations were not utilized. The provision of open materials and data was rare, with limited access to instruments and analysis scripts. Open access versions (preprints/postprints) were scarce. Trends analysis showed inconsistent changes over the years, with regional variations in open access publication. Conclusions: The low adoption of OSPs in psychometric studies of suicide calls for urgent action. Researchers must prioritize the use of preregistration, publication of preprints/postprints, and providing access to materials and data. Embracing a culture of open science will enhance transparency, reproducibility, and the impact of research in suicide prevention efforts.