Background: Prolonged nucleic acid conversion and false-negative results of real-time reverse transcription polymerase chain reaction (RT-PCR) might occur in some patients with COVID-19 MESHD rather than recurrence of infection. Here, we reported four cases of COVID-19 MESHD with prolonged nucleic acid conversion and false-negative results of RT-PCR in our institution.Case presentation: Case 1: A 36-year-old-male patient complained of coughing up phlegm one week before admission. His chest X-rays showed mild pneumonia MESHD in the right lung. His swab test was confirmed positive for SARS-Cov-2. Besides the last two consecutive negative results, he also had negative results of RT-PCR twice (the 6th and 8th tests) from a total of 11 swab tests. Case 2: A 54-year-old-male patient complained of shortness of breath MESHD that worsened with activity. He had a comorbidity of diabetes MESHD. His chest X-rays showed inhomogeneous opacity on bilateral paracardial and lateral aspects. His swab test was confirmed positive for SARS-Cov-2. Besides the last two consecutive negative results, he also had negative results of RT-PCR once (the 5th test) from a total of 8 swab tests. Case 3: A 47-year-old man presented with complaints of fever MESHD, cough MESHD, sore throat, and diarrhea MESHD. He had comorbidities of asthma MESHD and heart rhythm disorders MESHD. His chest X-rays showed bilateral pneumonia MESHD. His swab test was confirmed positive for SARS-Cov-2. Besides the last two consecutive negative results, he also showed negative results of RT-PCR twice (the 4th and 6th tests) from a total of 11 swab tests. Case 4: A 56-year-old-female complained of lethargy MESHD and diarrhea MESHD. She has a history of hyperthyroidism MESHD. His chest X-rays showed bilateral pneumonia MESHD. She was confirmed positive for SARS-Cov-2. Besides the last two consecutive negative results, she also had negative results of RT-PCR twice (the 2nd and 10th tests) from a total of 14 swab tests.Conclusions: Our cases further confirmed the occurrence of prolonged nucleic acid conversion and the possibility of false negative results of RT-PCR in patients with COVID-19 MESHD instead of recurrence of infection. These findings might have an implication on the management of patients with COVID-19 MESHD who have already clinically and radiologically recovered, particularly related to subsequent spreading of the infection in the community.