An LED socket string with multiple LED sockets and corresponding LED lamps that are spaced on the string unevenly or according to a user specification. Each of the LED sockets includes a socket base with grooves for coupling wires, and a socket cover for mating with the socket base. A lamp holder is integrally mounted onto the socket base for detachably retaining the LED lamp. A lamp spacer can be added to the lamp holder to accommodate the LED lamp.