There is an extremely complex nonlinear coupling relationship between urbanization and eco-environment. How to coordinate this relationship has become a global strategic problem and a worldwide scientific problem. First, based on theoretical analysis, this paper revealed the coupling, coupling relationship, coupling degree and coupling tower of interaction between urbanization and eco-environment. Second, by analyzing the main controlling factors, ten kinds of interaction modes between urbanization and eco-environment are summarized. Third, according to the strength of coupling degree, we have identified six coupling types, including low coupling, slight coupling, moderate coupling, high coupling, excellent coupling, and full coupling, which correspond to the random coupling, indirect coupling, loose coupling, synergistic coupling, tight coupling and control coupling, respectively. Then, urbanization and eco-environment coupling tower was formed. Finally, the theory of urbanization and eco-environment coupling coil was established. Through rotating the graph by 10°, we built 45 kinds of coupled graphs, including linear graph, index curve graph, logarithmic curve graph, double index curve graph and S-shaped curve graph. Different graphs represent different urban development modes, stages and characteristics. Among them, S-shaped curve coupled graph is optimal, and it reflects the best state of urbanization and eco-environment coupling. After that, we amplified the S-shaped coupled graph, and then constructed a coupler (UEC) based on the SD model and the complex relationship between different variables. The coupler consists of 11 regulatory elements and 201 variables, and can control the coupling state between urbanization coil and eco-environment coil. In general, the above control types include static control of multiple cities at the same time, dynamic control of a single city at different times, and dynamic control of multiple cities at different times. Through coupler control, urbanization coil and eco-environment coil can keep the best dynamic and orderly state. In addition, if one variable changes, the structure, function and simulation results of the coupler will also be affected. Finally, with the increase of control intensity, the coupler will gradually improve the coupling degree between urbanization coil and ecological environment coil.