A ceiling-embedded air conditioner comprising: a casing main body embedded in a ceiling; a square 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 disposed in the casing main body along a bottom side of the heat exchanger; 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 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; an air blowoff opening that is provided in the decorative panel and communicates with the air blowoff path; corner panels that are disposed at a respective corner portion between the adjacent air blowoff openings; a human sensor for detecting a human body that is exposed at a specific corner panel of the corner panels; a wind guide path that is provided in the decorative panel for communicating with the air blowoff opening and arranged between ends of the adjacent air blowoff openings; characterized by wind direction plates rotatably disposed in the air blowoff openings for guiding part of conditioned air blown therefrom to the wind guide path, said part of conditioned airflow being guided into a base end portion of the corner panel along inclined portions included in the wind direction plates; and windbreak ribs (41 and 42) that are erected from the specific corner panel to suppress a direct strike on the human sensor by the conditioned air flowing from the wind guide path toward the specific corner panel. a casing main body embedded in a ceiling; a square 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 disposed in the casing main body along a bottom side of the heat exchanger; 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 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; an air blowoff opening that is provided in the decorative panel and communicates with the air blowoff path; corner panels that are disposed at a respective corner portion between the adjacent air blowoff openings; a human sensor for detecting a human body that is exposed at a specific corner panel of the corner panels; a wind guide path that is provided in the decorative panel for communicating with the air blowoff opening and arranged between ends of the adjacent air blowoff openings; characterized by wind direction plates rotatably disposed in the air blowoff openings for guiding part of conditioned air blown therefrom to the wind guide path, said part of conditioned airflow being guided into a base end portion of the corner panel along inclined portions included in the wind direction plates; and windbreak ribs (41 and 42) that are erected from the specific corner panel to suppress a direct strike on the human sensor by the conditioned air flowing from the wind guide path toward the specific corner panel.