The invention discloses an apparatus and method for inducing water release of clay confined aquifer by constant drawdown, comprising: an unconfined aquifer sample loading barrel (1), a clay confined aquifer sample loading barrel (2) and a confined aquifer sample loading barrel (3) that are connected in succession from top to bottom; a retaining plate (6) for separating the clay confined aquifer sample loading barrel (2) and the confined aquifer sample loading barrel (3) is movably provided therebetween, a water incoming pipe is communicated with the sidewall of the top end of the confined aquifer sample loading barrel (3), and a water outgoing pipe (13) is communicated with the bottom end of the confined aquifer sample loading barrel (3). Through the apparatus and method provided by the invention, solved is the problem that in the traditional study on water release characteristics of a clay confined aquifer, it is not possible to effectively and actively control drawdown of adjacent confined aquifers and to measure the water release quantity of the clay confined aquifer.