The invention discloses a high-current non-contact electronic preheating relay, which can realize time limiting, short-circuit, over-voltage, overload and over-temperature protection control on powersupply to a diesel air inlet heating grid. A rectifier bridge is connected with a control end, and the rectifier bridge transforms the positive voltage or negative voltage input by the control end into a positive voltage through stable voltage rectification and then outputs the positive voltage; a singlechip receives the positive voltage output by the rectifier bridge, the singlechip has the functions of timing, temperature detection, short-circuit detection and voltage detection, a time limiting preset value, a temperature preset value and a voltage preset value can be set in the singlechip,and the singlechip is also connected with a high current input end; a booster pump is connected with the high current input end, and the booster pump is also connected with the singlechip; a high power transistor is connected with the high current input end and the booster pump respectively; and a high current output end is connected with the singlechip, the booster pump and the high power transistor respectively. The high-current non-contact electronic preheating relay can solve the problem of circuit burn-out caused by adhesion of contacts of a mechanical relay with the contacts.