The invention provides an iron-based mixed powder for powder metallurgy enabling the iron-based mixed powder to improve the machinability, without being accompanied by degrading the mechanical property of a sintered body. In order to obtain the purpose of the invention, the iron-based mixed powder comprises a mixture of an iron-based powder, a powder for an alloy, a powder for machinability improvement, while further adding lubricant. And, (1) the powder for machinability improvement comprises a manganese sulfide powder, and at least one selected from the group consisting of a calcium phosphate powder and a hydroxy apatite powder, or, (2) the powder for machinability improvement has an average particle diameter of 1 to 60 micrometers and is at least one selected from the group consisting of manganese sulfide powder and calcium fluoride powder.