Introduction: Suicidal ideation and behaviors are a leading cause of disability worldwide. Approximately 90 % of suicide completers have a diagnosable mood disorder. Extant literature reports rumination mediates functional impairment across mood disorders. Herein, we report the association between rumination and suicidality amongst persons with psychiatric disorders and healthy controls., Methods: Our systematic review and meta-analysis included relevant articles retrieved from Web of Science, OVID and PubMed from inception to March 20, 2024. Random effects model was used to calculate the correlation between rumination, suicidal ideation and attempt., Results: A total of 27 eligible studies were included in our systematic review and meta-analysis. Rumination (r = 0.25 [95 % CI: -0.03, 0.49]), reflection (r = 0.15 [-0.71, 0.83]) and brooding (r = 0.13 [-0.58, 0.73]) were nonsignificantly correlated with suicidal ideation in mood disorders. Suicide attempt history was significantly associated with greater odds of rumination in persons with depressive disorders (OR = 1.13 [0.42, 3.02]). In healthy controls, rumination (r = 0.30 [0.21, 0.38]), reflection (r = 0.23 [0.13, 0.32]) and brooding (r = 0.24 [0.12, 0.36]) were significantly correlated with suicidal ideation. Rumination also predicted lifetime history of suicide attempts in healthy controls (OR = 1.70 [1.16, 2.49])., Limitations: There were inadequate sample sizes of persons with different mood and psychiatric disorders which may have underpowered our ability to detect clinically meaningful associations., Discussion: Our study reports a transdiagnostic association between measures of rumination and suicidality. Future research vistas should parse the neurobiological substrates subserving rumination and identify targeted therapies and their association with general cognition and treatment response., Competing Interests: Declaration of competing interest Kayla M. Teopiz has received fees from Braxia Scientific Corp. Dr. Taeho Greg Rhee was supported in part by the National Institute on Aging (#R21AG070666; R21AG078972; R01AG088647), National Institute of Mental Health (#R01MH131528), and National Institute on Drug Abuse (#R21DA057540). Dr. Taeho Greg Rhee was supported in part by the National Institute on Aging (#R21AG070666; R21AG078972; R01AG088647), National Institute of Mental Health (#R01MH131528), and National Institute on Drug Abuse (#R21DA057540). Dr. Rhee serves as a review committee member for Patient-Centered Outcomes Research Institute (PCORI) and Substance Abuse and Mental Health Services Administration (SAMHSA) and has received honoraria payments from PCORI and SAMHSA. Dr. Rhee has also served as a stakeholder/consultant for PCORI and received consulting fees from PCORI. Dr. Rhee serves as an advisory committee member for International Alliance of Mental Health Research Funders (IAMHRF). Dr. Rhee was a co-Editor-in-Chief of Mental Health Science and has received honorarium payments annually from the publisher, John Wiley & Sons, Inc. Dr. Roger Ho has received National University of Singapore iHeathtech Other Operating Expenses (A-0001415-09-00). Dr. Rodrigo B. Mansur has received research grant support from the Canadian Institute of Health Research; Physicians' Services Incorporated Foundation; the Baszucki Brain Research Fund; and the Academic Scholar Awards, Department of Psychiatry, University of Toronto. Dr. Joshua D Rosenblat has received research grant support from the Canadian Institute of Health Research (CIHR), Physician Services Inc. (PSI) Foundation, Labatt Brain Health Network, Brain and Cognition Discovery Foundation (BCDF), Canadian Cancer Society, Canadian Psychiatric Association, Academic Scholars Award, American Psychiatric Association, American Society of Psychopharmacology, University of Toronto, University Health Network Centre for Mental Health, Joseph M. West Family Memorial Fund and Timeposters Fellowship and industry funding for speaker/consultation/research fees from iGan, Boehringer Ingelheim, Janssen, Allergan, Lundbeck, Sunovion and COMPASS. He is the Chief Medical and Scientific Officer of Braxia Scientific and the medical director of the Canadian Rapid Treatment Centre of Excellence (Braxia Health). Dr. Roger S. McIntyre has received research grant support from CIHR/GACD/National Natural Science Foundation of China (NSFC) and the Milken Institute; speaker/consultation fees from Lundbeck, Janssen, Alkermes,Neumora Therapeutics, Boehringer Ingelheim,Sage,Biogen,Mitsubishi Tanabe, Purdue, Pfizer, Otsuka, Takeda, Neurocrine, Sunovion, Bausch Health, Axsome, Novo Nordisk, Kris, Sanofi, Eisai, Intra-Cellular, NewBridge Pharmaceuticals,Viatris, Abbvie, Atai Life Sciences. Dr. Roger McIntyre is a CEO of Braxia Scientific Corp. Gia Han Le, Sabrina Wong, Hezekiah Au, Sebastian Badulescu, Hartej Gill, Shreya Vasudeva and Angela T.H. Kwan have no conflicts of interest to disclose., (Copyright © 2024 Elsevier B.V. All rights reserved.)