A carbon dioxide recovery apparatus, comprising: an absorbing tower adapted to discharge a rich liquid, the rich liquid resulting from absorbing carbon dioxide of a carbon-dioxide-containing gas introduced into the absorbing tower and into an absorbing liquid; a first heat exchanger adapted to discharge a first semi-lean liquid from which steam containing a portion of carbon dioxide is released by heating the rich liquid discharged from the absorbing tower; and a regeneration tower (102A, 102B) adapted to generate a lean liquid from which steam containing remaining carbon dioxide is released and separated by heating the semi-lean liquid discharged from the first heat exchanger and to return the lean liquid to the absorbing tower, wherein the first heat exchanger is adapted to utilize the lean liquid as a heat source and the apparatus further comprises either: a second heat exchanger adapted to heat the rich liquid discharged from the absorbing tower and discharge a second semi-lean liquid and adapted to utilize the steam containing carbon dioxide released in the regeneration tower as a heat source; or an upper loading layer in the regeneration tower adapted to heat the rich liquid discharged from the absorbing tower; and the apparatus being adapted such that the rich liquid discharged from the absorbing tower is split and supplied respectively to the first heat exchanger and either the second heat exchanger or above the upper loading layer, characterized in that the apparatus further comprises: a first gas-liquid separator provided outside the regeneration tower (102A, 102B) and adapted to separate the steam containing carbon dioxide and the first semi-lean liquid discharged from the first heat exchanger and supply the carbon-dioxide-containing steam to either the second heat exchanger as a heat source or below the upper loading layer in the regeneration tower as a heat source, a first separated semi-lean liquid line adapted to supply a first separated semi-lean liquid discharged from the first gas-liquid separator to the regeneration tower (102A, 102B). an absorbing tower adapted to discharge a rich liquid, the rich liquid resulting from absorbing carbon dioxide of a carbon-dioxide-containing gas introduced into the absorbing tower and into an absorbing liquid; a first heat exchanger adapted to discharge a first semi-lean liquid from which steam containing a portion of carbon dioxide is released by heating the rich liquid discharged from the absorbing tower; and a regeneration tower (102A, 102B) adapted to generate a lean liquid from which steam containing remaining carbon dioxide is released and separated by heating the semi-lean liquid discharged from the first heat exchanger and to return the lean liquid to the absorbing tower, wherein the first heat exchanger is adapted to utilize the lean liquid as a heat source and the apparatus further comprises either: a second heat exchanger adapted to heat the rich liquid discharged from the absorbing tower and discharge a second semi-lean liquid and adapted to utilize the steam containing carbon dioxide released in the regeneration tower as a heat source; or an upper loading layer in the regeneration tower adapted to heat the rich liquid discharged from the absorbing tower; and the apparatus being adapted such that the rich liquid discharged from the absorbing tower is split and supplied respectively to the first heat exchanger and either the second heat exchanger or above the upper loading layer, a first gas-liquid separator provided outside the regeneration tower (102A, 102B) and adapted to separate the steam containing carbon dioxide and the first semi-lean liquid discharged from the first heat exchanger and supply the carbon-dioxide-containing steam to either the second heat exchanger as a heat source or below the upper loading layer in the regeneration tower as a heat source, a first separated semi-lean liquid line adapted to supply a first separated semi-lean liquid discharged from the first gas-liquid separator to the regeneration tower (102A, 102B).