The invention relates to a diving equal head line observation device and a method using the diving equal head line observation device to implement. According to the diving equal head line observationdevice, a diving equal head line observation experimental system is established in a lab, a loose porous media in nature serves as a mock object, forming of diving, the characteristics of recharging,running off and discharging of diving, hydrodynamic condition and the like are simulated, the contour of water table during diving motion is observed through an experiment, the distribution pattern ofthe water table is determined to quickly master movement elements of all points in the seepage space. According to the diving equal head line observation device and the method, a novel technical meanis provided for observing and measuring water potential distribution along the way, size, flow and seepage flow rate of water potential at any point on a seepage profile, important basic informationis provided for regional hydrogeological condition survey, underground water level resource assessment, underground water hazards in engineering construction and environmental negative effect problems, and the diving equal head line observation device and the method have good economic and practical value and application prospects.