Background: Traditional platinum-based combination chemotherapy used as the standard first‐line treatment for advanced NSCLC poses potential safety risk for patients (pts) aged 70 years and above. Moreover, data on immune checkpoint inhibitors treating older pts with lung cancer in the current pivotal trials is limited. Metronomic chemotherapy (MCT) is the frequent administration of chemotherapy drugs at lower doses each time. Compared with traditional chemotherapy, MCT shows better safety profile and antitumor angiogenesis and immunomodulatory effects. Camrelizumab, an anti-PD-1 inhibitor, demonstrated encouraging efficacy in NSCLC (CameL study and CameL-sq study). Here, we designed a phase II trial to evaluate the efficacy and safety of camrelizumab plus metronomic oral vinorelbine (mOV) as first-line therapy for Chinese older pts with advanced NSCLC. Methods: Key inclusion factors were pts aged 70 years and above, histologically or cytologically confirmed unresectable stage III and IV NSCLC without positive EGFR mutation, ALK fusions or ROS1 fusions, ECOG performance status 0-2, no previous systematic treatment. Pts received camrelizumab (200mg, D1, q3w) combined with mOV (30mg, tiw1, day 1-3-5 per week) for 6 cycles, followed by camrelizumab monotherapy maintenance until disease progression or intolerable side effects. The primary endpoint was progression free survival (PFS). The secondary endpoints included overall survival (OS), objective response rate (ORR), disease control rate (DCR), duration of response (DoR) and safety. Results: From March 2021 to November 2022, 12 pts were evaluable for inclusion in the study. The median age was 77 (range: 70-85) with 8 (67%) males. Median follow-up was 7.2 months (range 2.8 months-22.1 months). The median PFS was 9.3 months (95%CI: 3.9 months-14.7 months). The one-year OS rate was 66.3%. The ORR and DCR were 50% (95%CI: 25.4%-74.6%) and 83.3% (95%CI: 50.9%-90.1%), respectively. Pts with positive or negative PD-L1 responded similarly to the treatment (respectively at 5/8 and 1/2 on ORR). The median OS and DoR have not been reached. Adverse events (AEs) with any grade were observed in 10 (83.3%) pts, of which grade III-IV AEs were observed in 2 (16.7%) pts with neutropenia and interstitial pneumonia, respectively. Immune-related adverse events (irAEs) occurred in 3 (25%) pts, of which grade III-IV irAEs occurred in one (8.3%) patient with interstitial pneumonia. No grade 5 adverse event happened. Conclusions: The regimen of camrelizumab plus mOV for the first-line therapy for older NSCLC pts showed initial promising efficacy and safety profile, which suggests it is worth further exploration. Clinical trial information: ChiCTR2100049487.