The invention provides a water channel assembly, a base and an air conditioner. The water channel assembly comprises an upper water channel and a lower water channel arranged on the lower side of theupper water channel, wherein the upper water channel and the lower water channel are of elongated slot structures and are in penetrating states along the length direction. The upper water channel shields the lower water channel in the vertical direction. According to the water channel assembly, by combining the upper water channel and the lower water channel up and down, the water channel assemblynot only can collect condensate water generated by a heat exchanger, but also can collect condensate water on the inner and outer side walls of the base of the air conditioner effectively to preventthe condensate water from dropping and the like, so that the using comfort of the air conditioner is improved. Moreover, as the upper water channel shields the lower water channel in the vertical direction, the probability about ash layer deposition in the lower water channel can be further reduced effectively, so that the conditions that the lower water channel is blocked by the ash layer and thelike can be prevented effectively to further prevent the condensate water from being accumulated and dropping to a using space, and therefore, the using comfort of an air conditioner user is improved.