Introduction COVID-19 virus continues to spread and die worldwide. Some studies examining hydroxychloroquine as a prophylactic agent reported that its efficiency and reliability have not been proven so that it must not be used for prophylaxis other than clinical researches. However we think that the results of this study we conducted in a local area will contribute to the literature data. Methods The study was designed as adult patients who were in follow-up taking HC due to their chronic diseases were included. 384 patients who were taking hydroxychloroquine regularly and 299 patients who were not taking hydroxychloroquine were included. The primary outcome of this study is to detect a positive PCR result in patients who received a PCR test and to determine the incidence rate and its course of the disease among those who were taking HC and those who were not taking hydroxychloroquine. Results The majority of the patients (median age: 51.8- range 17-89) were women and housewives. In the patient group using hydroxychloroquine, 22 patients were tested for PCR and only 2 positive patients were found. Covid-19 was detected in 24 (8.02%) of 65 (21.73%) patients who underwent PCR test at Control group (n = 299). PCR positivity was statistically lower in the HK group (n = 2, 0.52%, n = 24, 8.02%, respectively, p = 0.0001). Conclusions Our study supported the fact that there is a lower PCR positivity and symptoms are milder among patients who are using HC regularly, as compared to those who are not using hydroxychloroquine.