The invention discloses a chlorination furnace lining and a manufacturing method thereof. The chlorination furnace lining comprises a lining body. The lining body sequentially comprises an outer cast layer (2) and an inner cast layer (1) from outside to inside, and the outer cast layer (2) and the inner cast layer (1) are attached. Both the outer cast layer (2) and the inner cast layer (1) are formed by mixing phosphate castable and ceramic fiber cotton in a cast mode. The manufacturing method of the chlorination furnace lining comprises the steps that firstly, an outer cast layer mold plate is arranged in a shell (3), then the castable of the outer cast layer is prepared, the castable is poured into the mold plate, and demolding is conducted after the castable is dried, so that the outer cast layer (2) is formed; secondly, the inner cast layer (1) is manufactured through the same method; and thirdly, hot air at the temperature of 50 DEG C, hot air at the temperature of 100 DEG C, hot air at the temperature of 200 DEG C, hot air at the temperature of 500 DEG C and hot air at the temperature of 800 DEG C are guided into a chlorination furnace for 72 hours, 24 hours, 12 hours, 6 hours and 4 hours correspondingly. According to the chlorination furnace adopting the lining, the failure rate in the production process is low, the repair cycle is greatly prolonged, the maintenance cost is greatly reduced, and the service life of the chlorination furnace is greatly prolonged.