Introduction: GRIN-related disorders are characterized by pediatric-onset epilepsy and neurodevelopmental delay , but data from Chinese cohorts remain limited.. Objective: To characterize clinical, genetic and in silico structural features of GRIN-related epilepsy in Chinese children. Methods: We retrospectively analyzed 33 unrelated pediatric patients with pathogenic/likelypathogenic GRIN variants treated at Peking University First Hospital (2019–2025). Clinical phenotypes, genetic analysis, protein structure features and genotypephenotype correlations were evaluated. Results: Thirty-three probands (male-to-female ratio of 1.58:1) were enrolled. Median seizure onset was 1.58 years (IQR 0.36– 3.00); onset in GRIN2A was later than GRIN2B (2.75 vs 0.63 years, P < 0.01). Most patients (87 .9%, 29/33) had multiple seizure types; focal impaired awareness seizures predominated (87 .9%). Drug-resistant epilepsy affected 78.8% (26/33); only 12.1% (4/33) were seizure-free with ≤ 2 anti-seizure medications. Intellectual disability or developmental delay (ID/DD) occurred in 93.9% (31/33); GRIN2B patients had the most severe outcomes (100% ID/DD; ASD 25%). Electroencephalogram of GRIN2A patients often showed multifocal discharges and electrical status epilepticus in sleep (93.3% and 53.3%). We identified 33 unique de novo variants (72.7% missense; 15 novel); 83.3% missense variants (20/24) lay in high-constraint regions.Structural modeling showed LBD-S2 destabilization (median root-mean-square deviation 0.71 Å) and extracellular M3 displacement (median 1.03 Å). High-impact missense variants trended toward earlier onset and higher ASD prevalence but differences were not significant (P > 0.05). Conclusions: In this cohort, GRIN-related epilepsy is frequently drug-resistant with severe neurodevelopmental impairment. Missense variants cluster in constrained LBD/TMD regions; in silico LBD-S2 and M3 alterations potentially contribute to pathogenic mechanisms.