A lighting emitting diode (LED) device includes a first adjust module and a second adjust module. The first adjust module includes at least one first LED and has a first internal impedance having a first characteristic curve. A range covered by the first characteristic curve includes a first incomplete conduction region and a first conduction region. As the current increases from zero value and up, the first internal impedance decreases exponentially in the first incomplete conduction region, is approximately linear in the first conduction region. The second adjust module includes an impedance-providing component and an electronic component coupled in series. The second adjust module is coupled in parallel with the first adjust module. The second adjust module has a second internal impedance having a second characteristic curve. The first characteristic curve and the second characteristic curve match one another.