A method of manufacturing LED light string includes the steps of forming an LED light body from multiple serially connected printed circuit boards, fixing the LED light body to a base, and connecting a light-transmissible shell to the light body to form a cluster lamp; preparing a power cord, to which multiple lamp sockets are serially connected; fitting multiple cluster lamps to the lamp sockets on the power cord, so that the LED light bodies are made to emit light. A lampshade is detachably engaged with each lamp socket. The lampshade and the lamp socket may be differently designed to create romantic feeling. The number of LED light bodies on each cluster lamp and the number of cluster lamps on one LED light string may be varied as desired to increase the brightness of the light string while reduce the manufacturing cost of the LED light string.