The purpose of the present study was to examine how foreign language education may affect preschool children's native language development. The study was carried out with 70 children who were 48-60 months-old and attending a public preschool in Alanya, a district of Antalya, in Turkey. The research method of the study was Solomon Four-Group Design. Turkish Early Language Development Test (Tedil-3) was the data collection tool and used to measure children's native language skills. The experimental process took 8 weeks. Mann Whitney U and Wilcoxon Signed Ranks Tests were used in the analysis of the data, as the data did not show normal distribution. After determining the effect of the experimental procedure, the children included in the control groups also benefitted from the same experimental procedure for 8 weeks under the right to benefit from the experiment process? which has never been applied before in any studies in Turkey. Within the framework of the literature, findings were discussed and various suggestions were presented.