A sleeve unit for a motor of a ceiling fan includes a tubular member and a wire isolation member. The tubular member has a lateral slot extending through the tubular member from an inner periphery to an outer periphery of the tubular member. The lateral slot extends from a first axial end face towards a second axial end face of the tubular member along an axis of the tubular member. The wire isolation member includes an isolation plate unit delimiting a wire channel. The wire channel is located in the lateral slot. The isolation plate unit includes a stopper plate which is located in the lateral slot but does not come into a space delimited by the inner periphery of the tubular member.