The invention discloses a casting method of an epoxy resin covered rock core. The casting method comprises the following steps: determining a casting material type, wherein materials include an adhesive, a curing agent and a toughening agent; the adhesive is epoxy resin, the curing agent is polyamide resin and the toughening agent is dibutyl phthalate; mixing the adhesive, the curing agent and the toughening agent; uniformly and slowly injecting the mixed materials into a mold with the clamped rock core under the condition that the mold is horizontally arranged, and casting; finally, standing and cooling for 24h; detaching the mold and removing a casting finished product; and carrying out edge and corner polishing and beautifying. According to the casting method of the epoxy resin covered rock core, a manual rock core is subjected to external sealing and casting through the epoxy resin and has a good pressure bearing capability and stable rock core properties; and an application range of the rock cores is widened and displacement pressure is expanded to the use upper limit of 6MPa from the use upper limit of 1.0MPa, so that a foundation is laid for researches of indoor displacement experiments.