An LED ceiling lamp includes a primary illumination unit and at least one subsidiary illumination unit. The primary illumination includes a base and a connecting member to fix the base to a ceiling. Each of the at least one subsidiary illumination unit is fixed to the base and faces the ceiling. Each of the at least one subsidiary illumination unit comprises a circuit board with an LED unit, a lens and a reflector. The lens covers the circuit board. The circuit board and the lens are received in the reflector. The lens is configured for dividing the light beams from the LED units into several light groups. An aphotic area is formed between each two adjacent light groups. The reflector is configured for reflecting the several light groups on the ceiling.