A memory-in-pixel circuit and a driving method thereof, a liquid crystal display panel and a wearable device are disclosed. The memory-in-pixel circuit includes a latch circuit, a switch circuit and a selection circuit, all transistors included in the latch circuit are first type transistors, and the latch circuit is configured to latch a data voltage and generate a first latch signal and a second latch signal; the switch circuit is configured to provide the data voltage to the latch circuit when the switch circuit is turned on; the selection circuit is configured to apply the first selection signal or the second selection signal to a pixel under control of the first latch signal and the second latch signal, and to continue to apply the first selection signal or the second selection signal to the pixel when the switch circuit is turned off to achieve automatic update of the pixel.