 Line 3 and Line 4 are still under construction.In April 2019, the NDRC approved the Phase III Construction Plan of Zhengzhou Rapid Transit System (2019-2024), marking the start of the third round of construction.The plan includes the Line 3 Phase II, and the first phase of Line 6, Line 7, Line 8, Line 10, Line 12 and Line 14 with a total length of .