The invention discloses an air conditioner and a water receiving disc device thereof. The water receiving disc device comprises a flow gathering part and at least two water receiving parts; the flow gathering part and the water receiving parts are connected through flow guide parts, the flow gathering part is located below the water receiving parts, and a draining opening is formed in the flow gathering part. Condensate water borne by the water receiving parts can be guided to the flow gathering part through the flow guide parts in real time, much condensate water cannot be accumulated on the water receiving parts, the water receiving parts, the flow guide parts and the flow gathering part have the effect of bearing condensate water, the water receiving parts and the flow guide parts have the effect of temporarily storing condensate water, the flow gathering part has the effect of storing the condensate water, and therefore the water receiving disc device can thoroughly solve the water leakage problem.