A kind of pet drinking trough of automatic water supplement,System include: a floating drum,One floating drum operating bar,One connecting rod and a sealing valve rod,Floating drum group is connected to floating drum operating bar and following water-level lifting and interlocks floating drum operating bar actuation,Floating drum operating bar is pivoted to the connecting rod first end,Floating drum operating bar is set to act to interlock the connecting rod first end,Connecting rod second end is pivotally arranged on seat pivot ear in water fountain,Sealing valve rod is pivoted to connecting rod middle section,When water level decreasing declines floating drum drop-down floating drum operating bar and connecting rod first end,It obtains and interlocks the decline of sealing valve rod immediately,Water inlet conducting water fountain is set to obtain moisturizing immediately,When water level rising makes floating drum above push away floating drum operating bar and connecting rod first end above pushes away,It obtains and interlocks the rising of sealing valve rod immediately,Force the sealing valve rod because of the closely sealed water inlet of the pressure above pushed away,Up to sealing effect immediately.一種自動補水之寵物飲水器，係包括：一浮筒、一浮筒作動桿、一連桿及一止水閥桿，浮筒組接至浮筒作動桿並隨水位升降而連動浮筒作動桿作動，浮筒作動桿樞接至該連桿第一端，使浮筒作動桿動作得連動該連桿第一端，連桿第二端樞設至飲水器中座樞耳，止水閥桿樞接至連桿中段，當水位下降使浮筒下拉浮筒作動桿及連桿第一端下降時，得立即連動止水閥桿下降，使進水口導通飲水器得立即補水，當水位上升使浮筒上推浮筒作動桿及連桿第一端上推時，得立即連動止水閥桿上升，迫使該止水閥桿因上推之壓力密合進水口，達立即止水功效。
