A method of removing fluoride ion from waste liquid is provided, which includes providing a calcium source and a plurality of ceramic particles to a waste liquid containing fluoride ion for forming a plurality of calcium fluoride layers wrapping the ceramic particles. The calcium fluoride layers are connected to form a calcium fluoride bulk. The ceramic particles are embedded in the calcium fluoride bulk. The ceramic particles and the calcium fluoride bulk have a weight ratio of 1:4 to 1:20.