The Suicidal Ideation Questionnaire (SIQ) and the Suicidal Ideation Questionnaire- Junior (SIQ-Jr) were designed to capture suicidal ideation in adolescents and are often used in clinical trials. Our aim was to identify and appraise the published literature with respect to the validity, reliability, responsiveness and interpretability of the SIQ and SIQ-Jr. We conducted a systematic review following COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) guidelines to identify, appraise and synthesize published literature on measurement properties and interpretability of the SIQ and SIQ-Jr. We searched MEDLINE, Embase, APA PsycINFO, CINAHL, Web of Science, and Scopus from inception to May 16th, 2023 to identify sources relevant to our aim. We identified 15 sources meeting our eligibility criteria. The body of literature did not meet COSMIN standards to make recommendations for use with regards to these measurement instruments. Further research is needed, with a focus on content validity and structural validity, prior to recommending the SIQ and SIQ-Jr for use in clinical practice and in clinical trials. No specific grant funding was used for this review.