The KEGG pathways and GO analysis revealed that the differentially expressed miRNAs were related to viral processes or immunological pathways: miR-27a-5p acts on the TGF-beta pathway; miR-21-5p targets SMAD7, which is associated with the inflammatory response in the lung; miR-1246 acts on p53 pathway; and miR-4508 acts on ICAM2. In conclusion, the most relevant miRNAs, miR-27a-5p and miR-21-5p, were differently expressed in mild forms of COVID-19. This evidence concerns the gene SMAD7 and COVID-19.