The present invention provides a manufacturing method of a semiconductor device and a semiconductor device. A semiconductor device is provided, the semiconductor device includes a substrate, a stacked structure disposed on the substrate, the substrate comprises a cell array region, a peripheral circuit region and a middle region between the cell array region and the peripheral circuit region, the stacked structure comprises a first support layer, a first trench located in the middle region, a second support layer located on an upper surface of the stacked structure, wherein parts of the second support layer is disposed in the first trench, a portion of a sidewall of the first support layer directly contacts a portion of a sidewall of the second support layer, and a capacitor structure located in the cell array region.