The disclosure provides a printing layer trimming method and an electronic device using the same. The printing layer trimming method is suitable for the electronic device and includes steps as follows. An original layer is converted into a first printing layer. At least one data region of the first printing layer is identified to identify at least one blank region of the first printing layer. Then, the blank region of the first printing layer is trimmed off The trimmed first printing layer is further converted into a print head signal data and provided to a printing device to print a corresponding three-dimensional structure. The disclosure also provides another printing layer trimming method and an electronic device using the same for trimming a second printing layer generated according to a print head signal data and providing the second printing layer to a printing device to print a corresponding three-dimensional structure.