A ceiling-embedded air conditioner comprising: a casing main body embedded in a ceiling; a decorative panel mounted on the bottom surface of the casing main body; a turbo fan disposed in the casing main body; a heat exchanger disposed in the casing main body to surround the outer periphery of the turbo fan; a drain pan that is disposed in the casing main body along the lower side of the heat exchanger and includes a foamed resin drain pan main body and a resin drain sheet integrated with the drain pan main body on the heat exchanger side; an air suction path that is disposed in the center of the drain pan and reaches the turbo fan; an air blowoff path for conditioned air having passed through the heat exchanger, the air blowoff path being provided at four places of the drain pan along the sides of a virtual square surrounding the air suction path; an air suction opening that is provided in the decorative panel and communicates with the air suction path; rectangular air blowoff openings that are provided in the decorative panel and communicate with the air blowoff path, and wind direction plates that are rotatably provided in the air blowoff openings, wherein the air blowoff path is integrated with the drain pan, as a cuboidal shape having a pair of long side walls (64a and 64b) disposed with a predetermined space therebetween in parallel to the sides of the virtual square and a pair of short side walls (64c and 64d) connecting the ends of the long side walls (64a and 64b), an airflow guide vane (7, 7a, and 7b) is provided in the air blowoff path to direct part of the blown airflow of the conditioned air toward the short side of the air blowoff opening, and an attachment portion formed of the same material as that for the drain sheet and configured to attach the airflow guide vane (7, 7a, and 7b) is provided at an inflow-side opening portion of the air blowoff path. a casing main body embedded in a ceiling; a decorative panel mounted on the bottom surface of the casing main body; a turbo fan disposed in the casing main body; a heat exchanger disposed in the casing main body to surround the outer periphery of the turbo fan; a drain pan that is disposed in the casing main body along the lower side of the heat exchanger and includes a foamed resin drain pan main body and a resin drain sheet integrated with the drain pan main body on the heat exchanger side; an air suction path that is disposed in the center of the drain pan and reaches the turbo fan; an air blowoff path for conditioned air having passed through the heat exchanger, the air blowoff path being provided at four places of the drain pan along the sides of a virtual square surrounding the air suction path; an air suction opening that is provided in the decorative panel and communicates with the air suction path; rectangular air blowoff openings that are provided in the decorative panel and communicate with the air blowoff path, and wind direction plates that are rotatably provided in the air blowoff openings, wherein the air blowoff path is integrated with the drain pan, as a cuboidal shape having a pair of long side walls (64a and 64b) disposed with a predetermined space therebetween in parallel to the sides of the virtual square and a pair of short side walls (64c and 64d) connecting the ends of the long side walls (64a and 64b), an airflow guide vane (7, 7a, and 7b) is provided in the air blowoff path to direct part of the blown airflow of the conditioned air toward the short side of the air blowoff opening, and an attachment portion formed of the same material as that for the drain sheet and configured to attach the airflow guide vane (7, 7a, and 7b) is provided at an inflow-side opening portion of the air blowoff path.