A secure interaction method performed by a secure interaction device comprising a processor, a light emitting device, LED, indication device, a display unit, a memory and a frame buffer device, the method comprising: • setting, by the processor operating in a normal mode, the LED indication device and the display unit as being accessible by the processor operating in a secure mode (step A1); • loading, by the processor operating in the normal mode, an operating system to the memory operating in the normal mode, so that driver code starts and executes an application program (step A2) operating in the normal mode; wherein the memory operating in the normal mode can be accessed by the processor operating in the normal mode, and the memory operating in the secure mode can only be accessed by the processor operating in the secure mode; • receiving, by the processor operating in the normal mode, a secure processing request sent by the application program (step 101); • switching, by the processor operating in the normal mode, from the normal mode to the secure mode according to the secure processing request (step 102); • reading, by the processor operating in the secure mode, a security indicator from the memory operating in the secure mode (step B1); • controlling, by the processor operating in the secure mode, according to the read security indicator, the LED indication device to cyclically display different colors, wherein the LED indication device responds to control of the processor only when the processor operates in the secure mode (step B 21); • writing, by the processor operating in the secure mode, frame buffer information into the memory operating in the secure mode, wherein the frame buffer information is obtained, by the processor operating in the secure mode, from an interface provided by the frame buffer device (step C1), and the frame buffer device operates in normal mode; and • controlling, by the processor operating in the secure mode, the display unit to display a foreground layer and a background layer, wherein the frame buffer information that is read from the memory operating in the secure mode is displayed at the foreground layer and a background is displayed at the background layer, and the foreground and background layer are displayed in random different colors that are the same as the colors cyclically displayed by the LED indication device, and the display unit responds to control of the processor only when the processor operates in the secure mode (step D11). • setting, by the processor operating in a normal mode, the LED indication device and the display unit as being accessible by the processor operating in a secure mode (step A1); • loading, by the processor operating in the normal mode, an operating system to the memory operating in the normal mode, so that driver code starts and executes an application program (step A2) operating in the normal mode; wherein the memory operating in the normal mode can be accessed by the processor operating in the normal mode, and the memory operating in the secure mode can only be accessed by the processor operating in the secure mode; • receiving, by the processor operating in the normal mode, a secure processing request sent by the application program (step 101); • switching, by the processor operating in the normal mode, from the normal mode to the secure mode according to the secure processing request (step 102); • reading, by the processor operating in the secure mode, a security indicator from the memory operating in the secure mode (step B1); • controlling, by the processor operating in the secure mode, according to the read security indicator, the LED indication device to cyclically display different colors, wherein the LED indication device responds to control of the processor only when the processor operates in the secure mode (step B 21); • writing, by the processor operating in the secure mode, frame buffer information into the memory operating in the secure mode, wherein the frame buffer information is obtained, by the processor operating in the secure mode, from an interface provided by the frame buffer device (step C1), and the frame buffer device operates in normal mode; and • controlling, by the processor operating in the secure mode, the display unit to display a foreground layer and a background layer, wherein the frame buffer information that is read from the memory operating in the secure mode is displayed at the foreground layer and a background is displayed at the background layer, and the foreground and background layer are displayed in random different colors that are the same as the colors cyclically displayed by the LED indication device, and the display unit responds to control of the processor only when the processor operates in the secure mode (step D11).