A synchronous rectification control method suitable for a switching mode power supply with a synchronous rectifier is disclosed. A synchronous rectification controller with a first pin is provided. A pin voltage at the first pin is sampled to generate a sampled voltage. After the sampling, a detection current is provided and it flows out of the synchronous rectification controller from the first pin. Digital dead-time control signals are generated in response to the pin voltage and the sampled voltage. The synchronous rectifier is controlled to determine a dead time of the synchronous rectifier, based upon the digital dead-time control signals.