A method for detecting a receive end, wherein the method comprises: detecting, by using an electrical connection, whether a Peripheral Component Interconnect Express, PCI-E, transmit end is performing PCI-E receive end detection; transmitting (602, 704), by a first detection circuit, a first predetermined signal to a second detection circuit through optical transmission if it is detected that the PCI-E transmit end is performing the PCI-E receive end detection so that the second detection circuit detects, after receiving the first predetermined signal and by using an electrical connection, whether a PCI-E receive end is in position, and feeds back a second predetermined signal through the optical transmission if it is detected that the PCI-E receive end is in position; detecting (608, 710), by the first detection circuit, whether the second predetermined signal fed back by the second detection circuit through the optical transmission is received; and if a detection result is that the second predetermined signal fed back by the second detection circuit through the optical transmission is received, switching (610, 712) a resistor network connected to two terminals of the PCI-E transmit end separately from an OFF state into an ON state, so that the resistor network and capacitors at the two terminals of the PCI-E transmit end form an equivalent resistor-capacitor, RC, charging circuit, and then the PCI-E transmit end determines, according to the equivalent RC charging circuit, that the PCI-E receive end is in position; wherein both the first predetermined signal and the second predetermined signal are differential signals. detecting, by using an electrical connection, whether a Peripheral Component Interconnect Express, PCI-E, transmit end is performing PCI-E receive end detection; transmitting (602, 704), by a first detection circuit, a first predetermined signal to a second detection circuit through optical transmission if it is detected that the PCI-E transmit end is performing the PCI-E receive end detection so that the second detection circuit detects, after receiving the first predetermined signal and by using an electrical connection, whether a PCI-E receive end is in position, and feeds back a second predetermined signal through the optical transmission if it is detected that the PCI-E receive end is in position; detecting (608, 710), by the first detection circuit, whether the second predetermined signal fed back by the second detection circuit through the optical transmission is received; and if a detection result is that the second predetermined signal fed back by the second detection circuit through the optical transmission is received, switching (610, 712) a resistor network connected to two terminals of the PCI-E transmit end separately from an OFF state into an ON state, so that the resistor network and capacitors at the two terminals of the PCI-E transmit end form an equivalent resistor-capacitor, RC, charging circuit, and then the PCI-E transmit end determines, according to the equivalent RC charging circuit, that the PCI-E receive end is in position; wherein both the first predetermined signal and the second predetermined signal are differential signals.