The invention provides a cross-flow fan blade, a bearing fixing seat, a fan assembly and an air conditioner. The bearing fixing seat is provided with two end parts, wherein a water draining groove isformed in one end part. According to the cross-flow fan blade, the bearing fixing seat, the fan assembly and the air conditioner, water is prevented from entering the bearing fixing seat to corrode arubber bearing ring; a large number of noise which influences the user experience is avoided while the air conditioner runs.