An LED regulation circuit and method include a voltage transformation unit to receive DC power and provide a constant current to drive at least one LED and a pulse-width modulation unit to generate a driving signal to control the voltage transformation unit. The driving signal of the pulse-width modulation unit has an operation period. In the operation period, the driving signal drives the voltage transformation unit to output regular operation power. The pulse-width modulation unit is connected to a timing regulation unit which generates a regulation signal sent to the pulse-width modulation unit to regulate the operation period of the driving signal by adding a sleep period. In the sleep period, the driving signal lowers the power of the voltage transformation unit that drives the LED. Through alternately controlling the operation period and sleep period of the driving signal, continuous heat generation and heat accumulation can be reduced.