BACKGROUND This study aimed to investigate the effects on the gut microbiome of 40 infants delivered before term by cesarean section between antibiotic treatment and probiotics as assessed by 16S rRNA quantitative polymerase chain reaction (qPCR) sequencing. MATERIAL AND METHODS We divided 40 premature infants delivered by cesarean section into 4 groups according to exposure to antibiotics or probiotics: N group (No-probiotics and No-antibiotics), A group (antibiotics), P group (probiotics), and the AP group (antibiotics+probiotics). Fecal samples were collected on days 1, 3, and 10, and the microflora data were generated using 16S rRNA qPCR sequencing technology. The BugBase tool was used for phenotype prediction, the Tax4Fun tool was used for function prediction, and iPath software was used to predict the metabolic pathways of intestinal bacteria. RESULTS Antibiotics increased the abundance of pathogenic bacteria and reduced the replication and repair function (P=0.049), nucleotide metabolism function (P=0.047), and the purine metabolism pathways (P<0.05) of the gut microbiota. Probiotics increased the abundance of beneficial bacteria and the cellular community prokaryote function (P=0.042) and contributed to the Bifidobacteria biofilm formation. Probiotics alleviated the damage of antibiotics to the composition and function of the gut microbiota. CONCLUSIONS The findings from this study showed that antibiotic treatment of preterm infants born by cesarean section changed the gut microbiome, but that the use of probiotics could restore the normal microbiome, which supports that restoration of the normal gut microbiota may be achieved with probiotics.