The utility model discloses a heat injection and oil production device for an injection-production separation oil well. An insert seal is arranged at the middle part of a part of an injection-production pipe string corresponding to an oil layer; the part of the injection-production pipe string corresponding to the oil layer is divided into a bottom heat injection section and an upper oil production section; a sand control pipe string is provided with a sealing extension pipe at a position corresponding to the insert seal; an upper sand pipe corresponding to the upper oil production section is arranged at the upper part of the sealing extension pipe; a lower sand pipe corresponding to the bottom heat injection section is arranged at the lower part of the sealing extension pipe; the upper oil production section is provided with a cyclic sliding sleeve; the bottom heat injection section is provided with a check valve communicated downwards and a perforated tube; and the perforated tube is positioned below the check valve communicated downwards. The cyclic sliding sleeve can be replaced by a Y connector plus an extraction check valve. The utility model has the beneficial effects that the impact on the oil production layer caused by the injection of a heat medium is avoided, and the sand carrying capacity of produced oil is reduced, so that the impact of the produced oil on a sand control screen is reduced, the probability of the damage of the sand control screen is reduced, the oil production efficiency is improved, and the oil production period is prolonged.