Background: Furmonertinib (AST2818) is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) with central nervous system (CNS) penetration. Here we report the CNS response to furmonertinib versus gefitinib as first-line therapy in EGFR-mutated non-small cell lung cancer (NSCLC) patients in the FURLONG study. Methods: FURLONG was a randomized, double-blind, multi-center phase III study. Patients were randomized 1:1 to receive first-line furmonertinib 80mg/d or gefitinib 250mg/d. Brain scan was mandatory at screening. Patients with asymptomatic CNS metastases who did not require steroid treatment for 28 days or more were enrolled. A pre-planned CNS efficacy analysis was done using RECIST v1.1 in patients with measurable or non-measurable CNS lesions (cFAS) and patients with only measurable CNS lesions (cEFR). Results: Of 358 enrolled patients in the FURLONG study, 133 (37%) patients were defined as cFAS and 60 (17%) were defined as cEFR according to baseline brain scan judged by a blinded independent review committee (IRC). At the cut-off date of Sep 15, 2021, CNS progression-free survival (PFS) assessed by IRC in the cFAS population was significantly longer in the furmonertinib group than in the gefitinib group (20.8 vs 9.8 months, HR 0.40 [95% 0.23-0.71]; p = 0.0011). CNS PFS rate at 6, 12, 18 months were 91%, 77%, 63% in the furmonertinib group, and 76%, 46%, 34% in the gefitinib group. In the cEFR set, confirmed CNS objective response rate was 91% in patients with furmonertinib and 65% in patients with gefitinib (p = 0.0277), and CNS disease control rate were 100% vs 84% (p = 0.9420), respectively. The mean best percentage change in the sum of target CNS lesion size from baseline in cEFR was -61.8% in the furmonertinib group versus -38.7% in the gefitinib group (p = 0.0011). Conclusions: Furmonertinib showed CNS efficacy as first-line therapy in EGFR-mutated NSCLC patients with CNS lesions. Patients treated with furmonertinib had a reduced risk of CNS progression or death, a higher CNS ORR and a deeper CNS response compared with gefitinib. Clinical trial information: NCT03787992.