Background To evaluate the efficacy and safety of pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) in preventing neutropenia during multiple cycles of chemotherapy in patients with non-small cell lung cancer (NSCLC). Method In a multicenter, prospective, randomized trial, patients with NSCLC were randomly assigned in a 2:1 ratio to treatment group (PEG-rhG-CSF as primary prophylactic therapy) or control group. Patients in the control group were administered rhG-CSF when white blood cell count was <2.0 x 10(9)/L or absolute neutrophil count <1.0 x 10(9)/L. The primary endpoint was the incidence of grade 3/4 neutropenia. Secondary endpoints included the incidence and duration of grade 3/4 neutropenia in each cycle, the incidence of febrile neutropenia (FN), delay rate of chemotherapy, prolonged time of chemotherapy, and safety. Results Between January 2019 and July 2021, 130 patients were enrolled (treatment group: n = 87, control group: n = 43). The incidence of grade 3/4 neutropenia in the treatment group was significantly lower than that in the control group (1.15% vs. 11.63%, p < 0.05). The mean duration of grade 3/4 neutropenia for the treatment and control group was 2.00 and 3.75 days, respectively. There were no statistical differences in the incidence of FN, delay rate of chemotherapy, prolonged time of chemotherapy, and antibiotic use between the two groups (all p > 0.05). Adverse events were reported in 47.13% of patients in the treatment group and 48.84% patients in the control group. Conclusions Primary prophylactic treatment with PEG-rhG-CSF could reduce the incidence of neutropenia in patients with NSCLC during multiple cycles of chemotherapy, with acceptable safety and tolerability.