A Light Emitting Diode (LED) fluorescent cover comprises the following components by weight: 90-96% of single-component solid silicone rubber, 3-8% of fluorescent powder and 1-2% of vulcanizer; and the preparation method includes the following steps: step 1): using mixed compound of the single-component solid silicone rubber, as well as the fluorescent powder and the vulcanizer as raw material to mix, standing for 2-4 h after mixing with open mill or internal mixer; step 2): controlling temperature, pressure and vulcanization time of vulcanizing machine according to size of the fluorescent cover mold, using the vulcanizing machine to carry out first vulcanization to the raw material that is obtained from the step 1) and placed in the fluorescent cover mold; step 3): with combined action of blower gun, taking the fluorescent cover out slowly; step 4): baking the semi-finished product in a closed space at a temperature of 150-200° C. for 1-2 h.