An audible post-it system includes a post-it note printed with an index and an optical reading and recording device having an optical module, a switch, a storage device, an audio recording device, an audio playing device and a processor. The optical reading and recording device reads an image of the index. When the optical reading and recording device is at a recoding state, the processor receives the image of the index and obtains the index, then receives a digital audio outputted by the audio recording device to match the index with the digital audio, and stores the digital audio based on the index. When the optical reading and recording device is at a playing state, the processor receives the image of an index and retrieves the index, then reads a digital audio based on the index, and sends the digital audio to the audio playing device for playing.