As a rich source of polysaccharides, pumpkin pulp was used for the production of oligosaccharides. To investigate the prebiotic potential of the oligosaccharides, prepared by acid hydrolysis of polysaccharides from pumpkin pulp, the effect of the oligosaccharides on lactobacilli growth was studied. The oligosaccharides were composed of galactose (99.03%) and glucose (0.97%). The molecular weight distribution of the oligosaccharides showed a larger part of low molecular weight fraction in a range from 5000 to 324 Da than the polysaccharides, which gave the oligosaccharides higher solubility. The oligosaccharides showed good resistance to hydrolysis by artificial human gastric juice and α‐amylase, compared to the reference prebiotic inulin, and considerable capability to stimulate the growth of lactobacilli. In vitro studies showed that the number of lactobacilli was significantly greater than those in control medium when they were cultured in the medium supplemented with the oligosaccharides (P < 0.05), and there was no significant difference at the oligosaccharides group and the inulin group (P < 0.05).