The invention discloses RT-LAMP detection primer pairs, a detection kit and a detection method for infectious haematopoietic necrosis virus (IHNV). The detection primer pairs comprises a pair of outer primers, a pair of inner primers and a pair of loop primers; the detection kit comprises primer liquid, reaction liquid, DNA polymerase, reverse transcriptase and control; and the detection kit also can contain a color developing agent. The detection method comprises the following steps: extracting to-be-detected virus RNA, and amplifying a sample RNA template at the temperature of 63-65 DEG C by utilizing reverse transcription activity of reverse transcriptase and adopting six specific primers and one DNA polymerase with strain displacement activity, wherein the pg grade of pure virus RNA can be detected; and identifying by adding SYBR Green I ESE-Quant-tube Scanner instrument detection, or utilizing a turbidity meter for observing change of turbidity of sediments in a reaction tube, so as to judge whether to carry out amplification or not and determine whether the to-be-detected sample contains IHNV RNA or not. The RT-LAMP detection primer pairs, the detection kit and the detection method for the IHNV have the advantages of quickness, high efficiency, easy operation, high specificity, high sensitivity, easy identification and applicability to field detection and are applicable to popularization and application.