the present invention discloses a photonic crystal memory type all - optical “ aor ” logic gate , and including photonic crystal structure ; the photonic crystal structure includes two input ports , an output port and an idle port ; a first input end and a second input end of the photonic crystal structure are respectively connected with a signal a and a signal b . the present invention has the advantages in high contrast of high and low logic output , high in computing speed , strong in anti - interference capability , and ease of integration with other optical logic elements .