Introduction: There is little evidence regarding the knowledge of the National Superintendence of Health (Superintendencia Nacional de Salud, SUSALUD), and health rights. The objective of this study was to determine the factors associated with filing complaints in patients treated at a Level III-1 health facility of the Ministry of Health (MINSA) in Lima 2019. Methods: Cross-sectional study on Internal Medicine patients treated at a Level III-1 health facility of MINSA, Lima, Peru in 2019. We used a modified survey taken from the complaints and knowledge about SUSALUD section from the questionnaire of the National Health User Satisfaction Survey (ENSUSALUD 2016). Prevalence ratios were estimated through simple and multiple regression. Results: Of 250 patients, the average age was 52 years and most of them were women (61.2%). Of the total, 37.3% made some health care complaints. The majority of the patients knew about the complaints book (66.4%), but only 30% knew about SUSALUD. Knowing SUSALUD (PR=3.33, CI95%: 1.81-6.11), the right to access health services (PR=1.15, CI95%: 0.41-3.29) and the right to be informed (PR=2.65, CI95%: 1.07-6.60) were associated with a greater frequency of filing health care complaints. Conclusions: The frequency of complaints due to care problems is high. The knowledge about SUSALUD, the right to access health services and the right to be informed were positively associated with filing any type of complaint. Keywords: Knowledge, complaints, health care, hospitals (Source: DECS)