The paper questions the traditional method for the calculation of the water level in the conventional observation wells for three-dimensional groundwater flow, and proposes that the Hantush -Бочевер equation, a pure mathematical method, is lacking in the basis of physics. The analysis of the formation mechanism of water level in the observation wells shows that the flux is zero only at the mouth of three-dimensional groundwater observation well, but the interior of the well contains actually "discharge" and "recharge" from the aquifers; that the water level in one homogeneous aquifer may have the same essential features as the multilayer well has; that the water level in the multilayer well is not mixed, and that the distribution of the head and flow in the multilayer well conforms to its own mechanism. Generally speaking, the observation well in the three-dimensional groundwater flow may not be described with the line sinks and line sources, nor can it be assumed that the flow in the observation well is determined by the laminar flow (linear flow) that has been proposed in recent years. However, the "seepage-pipe coupling model" and "equivalent hydraulic conductivity" (EHC) presented by the author in 1993 can be used to simulate very conveniently and effectively the three-dimensional groundwater flow. For the further illustration, the Hantush-Бочевер equation can only be approximately used in the conditions where the diameter of observation well is more than 0.2 m and that the distance between the well and the observation well is more than 10-20 m.