Importance: Systematic review will improve understanding of nonsurgical facial feminization techniques, which are useful alternatives or adjuncts to surgical gender affirmation. Objective: To determine the effectiveness of nonsurgical facial feminization techniques in patients seeking gender-affirming feminization by reviewing the literature for patient-reported, subjective, and objective outcomes of feminization. Evidence Review: A comprehensive database search was conducted through July 28, 2022. A total of 264 titles and abstracts were screened by two independent reviewers in Covidence. Of all, 48 met the inclusion criteria for full-text review, and 20 articles were included in the final data extraction. Findings: The most described nonsurgical facial feminization techniques were neurotoxins, fillers, and hair removal. Techniques were derived from cisgender cosmetic procedures to achieve feminine qualities. The most common study type was expert opinion or literature reviews. There were only two studies that analyzed measurable nonsurgical facial feminization techniques. Conclusions and Relevance: There is a lack of high-quality prospective research and randomized, controlled trials specific to the transgender patient population that evaluate outcomes, patient satisfaction, or complications. Such studies are needed to inform evidence-based practices.