The invention discloses a pyridazinoquinoxaline diamine Schiff base cobalt ion fluorescent probe and a preparation method thereof. The present invention utilizes camphor derivative camphorquinone as a raw material, and carries out cyclization reaction with 2,3-diaminomaleonitrile to obtain 5,9,9-trimethyl-5,6,7,8-tetrahydro-5, 8-bridge methylene quinoline-2,3-dicarbonitrile; then carry out condensation cyclization reaction with hydrazine hydrate to obtain 6,11,11-trimethyl-6,7,8,9-tetrahydro-6 , 9-bridge methylene pyridazino[4,5-b]quinoxaline-1,4-diamine; and then carry out condensation reaction with 2-hydroxyl-1-naphthaldehyde to obtain 6,11,11-three Methyl-6,7,8,9-tetrahydro-6,9-methanopyridazino[4,5-b]quinoxaline-1,4-diamine condensed 2-hydroxy-1-naphthalene Formaldehyde bis-Schiff base. The compound can rapidly and exclusively bind Co at room temperature 2+ Complexation occurs, so that the orange-yellow fluorescence of the solution is quenched, and the color of the solution changes from orange-red to dark red under sunlight. It can be used as a fluorescent probe for detecting cobalt ions, and has a good application prospect.