The increasing frequency and intensity of extreme climatic compound events pose significant challenges to agricultural production in arid and semi-arid regions, particularly in the Hexi Corridor-a typical arid oasis in Northwest China where water scarcity is the core constraint for seed maize (Zea mays L.) cultivation, a key local industry. Therefore, understanding the comprehensive effects of irrigation, planting date, and extreme climate events on seed maize yield traits is essential for developing adaptive strategies to cope with aridity and climate risks. This study conducted a six-year field experiment (2019-2024) in Ganzhou District, Zhangye City, using the local seed maize variety "Zhengdan-958". Treatments included two irrigation levels (I1: 50 % of the local traditional irrigation quota; I2: 100 %) and five planting dates (PD1: 20 days earlier than local typical; PD2: 10 days earlier; PD3: local typical; PD4: 10 days later; PD5: 20 days later), aiming to assess impacts of these factors on seed maize yield traits. The aim was to assess the impacts of irrigation, planting date, climatic factors, and extreme climate events on seed maize yield traits. Results showed that increasing irrigation to I2 significantly enhanced the number of kernels per ear (KNPE), 100-kernel dry weight (HKDW), and grain yield by 24.48 %, 16.06 %, and 38.84 %, respectively. Planting 10 days earlier achieved the highest KNPE and grain yield while mitigating high-temperature stress during late growth stages. Growing degree days (GDD) emerged as the primary driver of yield formation, whereas extreme climatic compound events (cold and dry days, CDD; hot and dry days, HDD; hot and wet days, HWD) explain 50.91-60.1 % of yield losses. Among them, HDD from flowering to maturity (FD-MD) caused the greatest yield losses, accounting for 19.43 %. Using linear mixed models and structural equation models, we found that key climate factors (GDD, precipitation, CDD and HDD) directly and indirectly affected seed maize yield by regulating KNPE and HKDW, with HKDW playing a particularly crucial role in determining final yield. This study provides a quantitative assessment of seed maize vulnerability at specific growth stages and proposes a two-stage adaptation strategy: early planting to avoid extreme hightemperature events during reproduction and enhanced irrigation to mitigate cold and dry stress during vegetative growth. These findings offer a viable pathway for climate-smart agricultural practices in arid regions.