The invention discloses an insulating paint for a motor. The insulating paint consists of the following components: 100 parts of modified epoxy resin, 0.1 to 0.5 part of initiator, 10 to 30 parts of activated thinner, 10 to 30 parts of nitrogen-containing hyperbranched polyphosphonate, 5 to 20 parts of curing agent, and 0.1 to 1 part of curing accelerator, wherein the modified epoxy resin is prepared by reacting epoxy resin with the epoxy equivalent weight less than or equal to 200g/mol with C2-C12 aliphatic anhydride at the temperature of between 30 and 50 DEG C. The insulating paint for themotor has the advantages of high stability, high adhesive strength, good insulating property, high mechanical strength, good heat dissipation, good electromagnetic adhesive property and no verdigris,and is used for a high temperature motor so as to form an insulating material with the oxygen index over 30 percent. Therefore, the insulating paint can simultaneously meet various requirements on the insulating paint for the motor, and also has low cost.