For the past, the substation planning mostly focused on the target year planning, and the process from the current year to the target year was always overlooked. Although there were few studies taking these into account, they mainly based on the current year and positively pushed to target years, this method was hardly to be operated and it ignored the importance of the target year planning. In this work, a method of calculating the mid-years(years between the current year and the target year) substation planning based on the target year planning is proposed, the transportation model is used to calculate the power supply range. This method set an adjustable parameter to meet the needs of users, such as establishing substations and occupying plots or large-capacity substations preferentially. Based on this method, Mid-years substation planning is realized effectively.