<p>This paper aims to examine the impact of the Syrian refugee influx on native fertility in Türkiye. Currently, Türkiye is hosting over 3.6 million Syrian refugees, particularly in the southeastern regions, leading to significant demographic changes. However, the impact of the refugee crisis on native fertility has not been examined yet. This paper fills a critical gap in the literature by investigating the effect of refugees on native fertility, a topic that has received limited attention. To estimate the causal effect, we employ a difference-in-differences design and synthetic control methodology. This study makes significant contributions to understanding the impact of migration on native fertility rates by revealing a considerable positive impact of Syrian refugees on native fertility behavior, on average, the TFR in treated provinces increased by 0.13 relative to control provinces following the refugee influx in provinces with 4% or higher refugee density, and by 0.10 in provinces with 2% refugee density. Synthetic control results also support strong evidence of these findings. Based on the synthetic control results, we observed a significant impact of the refugee shock on the nine highly refugee-intensified Eastern provinces. The provinces most affected include Şanlıurfa, Gaziantep, Kilis, and Adıyaman.</p>