Graphene is one of the most promising next-generation gas sensing material due to its large surface-to-volume ratio, excellent gas adsorption properties, and high carrier mobility. To explore an efficient way for enhancing its gas sensing performance, in this study the effect of strain on graphene's gas adsorption behavior was investigated. Monolayer graphene was synthesized via low pressure chemical vapor deposition, and a flexible gas sensor was fabricated on a polyimide substrate. The sensor exhibited good stability under compressive strain and demonstrated increased sensitivity to NO₂ and NH₃ gases. The findings suggest that strain can be utilized to improve the performance of graphene-based gas sensors.