A ceiling type indoor unit of air conditioner comprising: a case on which a discharging hole is formed; a first vane disposed at the discharging hole; a vane motor assembled to the case and configured to provide a driving force to the first vane; a driving link assembled relatively rotatably with the case and coupled with the vane motor and configured to transmit the driving force of the vane motor to the first vane; a first vane link assembled relatively rotatably with the case and with the first vane; a support bracket coupled to the case and disposed at the discharging hole; a support link disposed between one end and the other end in a longitudinal direction of the first vane and assembled relatively rotatably with the first vane and with the support bracket, characterized in that the driving link comprises one side driving link disposed at one side of the discharging hole and comprises the other side driving link disposed at the other side of the discharging hole, wherein the first vane link comprises one side first vane link disposed at the one side of the discharging hole and comprises the other side first vane link disposed at the other side of the discharging hole, wherein the support link comprises a first support bracket disposed close to the one side between the one side and the other side of the discharging hole and comprises a second support bracket disposed close to the other side, wherein the support link comprises a first support link assembled relatively rotatably with the first vane and the first support bracket and comprises a second support link assembled relatively rotatably with the first vane and the second support bracket. a case on which a discharging hole is formed; a first vane disposed at the discharging hole; a vane motor assembled to the case and configured to provide a driving force to the first vane; a driving link assembled relatively rotatably with the case and coupled with the vane motor and configured to transmit the driving force of the vane motor to the first vane; a first vane link assembled relatively rotatably with the case and with the first vane; a support bracket coupled to the case and disposed at the discharging hole; a support link disposed between one end and the other end in a longitudinal direction of the first vane and assembled relatively rotatably with the first vane and with the support bracket, characterized in that the driving link comprises one side driving link disposed at one side of the discharging hole and comprises the other side driving link disposed at the other side of the discharging hole, wherein the first vane link comprises one side first vane link disposed at the one side of the discharging hole and comprises the other side first vane link disposed at the other side of the discharging hole, wherein the support link comprises a first support bracket disposed close to the one side between the one side and the other side of the discharging hole and comprises a second support bracket disposed close to the other side, wherein the support link comprises a first support link assembled relatively rotatably with the first vane and the first support bracket and comprises a second support link assembled relatively rotatably with the first vane and the second support bracket.