A carbon-containing material gasification system includes: a gasifier that includes a combustion stage and a gasification stage, and generates generated gas; char providing means that separates char from the generated gas, and provides the combustion stage with the char, the combustion stage including carbon-containing material combustion means and char combustion means; and distributing ratio setting means that sets, according to a ratio of distributing material defined in Expression [1], a ratio of distributing oxidizing agent defined in Expression [2] to be smaller as the ratio of distributing material increases. (ratio of distributing material)=(providing amount of the carbon-containing material for gasification stage)/(total providing amount of the carbon-containing material to gasifier)  [1] (ratio of distributing oxidizing agent)=(providing amount of the oxidizing agent to oxidize carbon-containing material for the combustion stage)/(total providing amount of the oxidizing agent to the combustion stage)  [2]