Based on the price data of 19,211 second-hand houses based in the Fuyang District and West Lake District from the years of 2014, 2015, and 2019, along with the characteristic data of second-hand houses, this paper studies the influence of the city-county merger of Fuyang. Through a combination with the double differences model and the hedonic price model, it was found that the city-county merger had time and spatial effects on housing prices. With regard to time effect, the city-county merger hindered the growth of Fuyang’s housing prices in the short term, while it had a promoting effect on Fuyang’s housing prices in the long term. With regard to the spatial effect, it was found that in the long term, the effect of the city-county merger on the promotion of Fuyang’s housing prices increased first and then weakened with an increase in distance from the West Lake District. In addition, it had the strongest effect on the promotion of housing prices within 3–6 km of the West Lake District.