The invention discloses a cathode material for a room temperature sodium-sulphur battery, and a preparation method thereof. The cathode material is formed by compounding a sulphur composite active material and a conductive additive with a conduction effect according to a weight ratio of (8 to 10):1. The preparation method comprises the following steps: compounding an active substance sulphur with an organism or an inorganic substance by adopting one of a solvent solution method, a high-temperature compounding method, a high-energy ball milling method, a sand grinding method, a grinding method, a vapor deposition method and a liquid deposition method to be a sulphur composite active material; mixing the sulphur composite active material and the conductive additive according to the weight ratio of (8 to 10):1 to obtain the cathode material for the room temperature sodium-sulphur battery. The room temperature sodium-sulphur battery adopting the cathode material disclosed by the invention has high capacity density; the cathode material takes an important effect on the battery capacity, and also has good circulating performance; the cathode material prolongs the service life of the battery and has the advantages of good safety, low price, high efficiency and the like when being used in the room temperature sodium-sulphur battery.