A testing device and method thereof verifies performance of a non-invasive physiological information detecting device. The testing device incorporates a first layer to modulate one or more electromagnetic signals, e.g., light, emitted from the non-invasive physiological information detecting device in a first predetermined manner and a second layer to process the electromagnetic signal from the first layer such that the modulated signal received at the physiological information detecting device simulates a change in the electromagnetic signal during a real detecting process. In one embodiment, the second layer modulates one or more electromagnetic signals from the first layer in a second predetermined manner, wherein at least one of the first and second layers modulates one kind of the electromagnetic signals. In another embodiment, the first layer scatters different kinds of electromagnetic signals with different scattering ratios, and the second layer absorbs the electromagnetic signals passing through the first layer.