In this work, the RuCu bimetal was used in gas-sensitive material for the first time. We successfully synthesized small-sized RuCu bimetallic nanoparticles using a simple co-reduction method to modify SnO2 nanoparticle clusters. The structure morphologies of the synthetic materials were characterized and its gas sensing properties were tested in detail. Among them, the sensor based on 0.3 wt% RuCu modified SnO2 materials showed excellent sensing performance of n-pentanol. The response value Ra/Rg was 217.83 toward 50 ppm at 200 ◦C, the response and recovery time for 200 ppb gas were 28 s and 31 s, respectively. Meanwhile, the sensor also had considerable repeatability and moisture resistance. Its excellent gas performance is attributed to the synergistic effect of RuCu bimetal, which has better catalytic activity than single metal. In addition, the chemical sensitization and elec tronic sensitization of RuCu bimetal also make a great contribution. The RuCu-SnO2 gas sensor has potential applications in the real-time monitoring of n-pentanol.