The amount of time people spend inside buildings is significant. Indoor environment quality deficiencies in some of these buildings may affect the health of its users. Therefore, a systematic literature review has been conducted to assess the quality of indoor environments in existing buildings in Latin America. The objectives of this review are (1) identifying countries and building types whose indoor environment quality has been analyzed the most, (2) identifying most used evaluation strategies, (3) identifying comfort types and most evaluated variables, and (4) determining whether or not Latin American buildings are comfortable and what local factors contribute to that effect. From the 100 selected papers for this analysis, it was noted that Brazil and Argentina led the studies on residences and schools. It was also noted that hygrothermal comfort was the most analyzed comfort type, with temperature and humidity leading the number of studies. Finally, this review shows a lack of studies including buildings whose users are sensitive to indoor environmental quality, such as nurseries, senior homes, or health facilities. Additionally, there is a sustained discrepancy between objective measuring methods and user perception. Furthermore, a detailed analysis of 88 buildings shows that in Latin America, 67.5% of buildings are uncomfortable; thus, it is necessary to improve the designs and regulatory standards, to educate users, and to improve building monitoring management at the operational stage.