Objective To investigate the effect of compound Fufangteng mixture-containing serum on the proliferation of bone marrow mesenchymal stem cell (BMSC) and its mechanism. Methods Rat BMSC were isolated, cultured and purified in vitro by direct adherence method. Cell morphology was observed. Surface markers were identified by flow cytometry. The rats were treated with compound Fufangteng mixture at a dose of 3 mL/(kg·d) by gavage for 14 d, and then the drug-containing serum was collected. BMSC were divided into the blank control group, drug-containing serum group, Notch1 small interfering ribonucleic acid (siRNA) group and Notch1 siRNA+drug-containing serum group. The proliferation rate of BMSC was detected and the relative expression levels of Notch1 signaling pathway-associated messenger ribonucleic acid (mRNA) and proteins were measured in each group. Results Microscopic observation showed that the first generation BMSC were seen in the long spindle shape, and grown in the parallel or spiral pattern. The third generation BMSC positively expressed CD90 and CD44, whereas were negative for CD45. Compared with the blank control group, the proliferation rate of BMSC in the drug-containing serum group and Notch1 siRNA+ drug-containing serum group was significantly increased, whereas that of BMSC was significantly decreased in the Notch1 siRNA group (all P < 0.05). Compared with the Notch1 siRNA group, the proliferation rate of BMSC was significantly increased in the Notch1 siRNA+drug-containing serum group (P < 0.05). Compared with the blank control group, the relative expression levels of Hey1 and Delta-like ligand (DLL)1 mRNA and proteins were significantly up-regulated in the drug-containing serum group, whereas those were significantly down-regulated in the Notch1 siRNA group and Notch1 siRNA+drug-containing serum group (all P < 0.05). Compared with the Notch1 siRNA group, the relative expression levels of Hey1 and DLL1 mRNA and proteins were significantly up-regulated in the Notch1 siRNA+drug-containing serum group (all P < 0.05). Conclusions Compound Fufangteng mixture-containing serum may promote the proliferation of rat BMSC, and its mechanism is probably associated with the activation of Notch1 signaling pathway.