An analyzing device having a microchannel structure that is rotationally driven around an internally set axial center and transfers a sample liquid towards an internal measurement spot by a centrifugal force accompanying the rotational drive, and which is used for reading involving accessing a reactant at the measurement spot, the analyzing device comprising: an inlet which collects the sample liquid from a leading end of the inlet; a guide section formed so as to extend circumferentially inward from the inlet and in which a capillary force acts; a capillary cavity as a sample measuring section that quantitatively measures, by a capillary force, a fixed amount of the sample liquid collected from the inlet via the guide section; a receiving cavity that accepts the sample liquid transferred from the capillary cavity, and a bent section forming a recess, the bent section being formed at a connected section of the guide section and the capillary cavity so as to change a passage direction, characterized in that the inlet protrudes circumferentially outward from the axial center; and the analyzing device further comprises: a protective cap that is provided outside the inlet and holds sample liquid scattered from the guide section due to the centrifugal force; and wherein the sample liquid held in the capillary cavity is configured to be broken due to the centrifugal force at the position of the bent section, thereby a fixed amount of the sample liquid is transferred to the receiving cavity and an amount of the sample liquid to be discharged into the protective cap is limited to just a minute amount in the guide section. an inlet which collects the sample liquid from a leading end of the inlet; a guide section formed so as to extend circumferentially inward from the inlet and in which a capillary force acts; a capillary cavity as a sample measuring section that quantitatively measures, by a capillary force, a fixed amount of the sample liquid collected from the inlet via the guide section; a receiving cavity that accepts the sample liquid transferred from the capillary cavity, and a bent section forming a recess, the bent section being formed at a connected section of the guide section and the capillary cavity so as to change a passage direction, characterized in that the inlet protrudes circumferentially outward from the axial center; and the analyzing device further comprises: a protective cap that is provided outside the inlet and holds sample liquid scattered from the guide section due to the centrifugal force; and wherein the sample liquid held in the capillary cavity is configured to be broken due to the centrifugal force at the position of the bent section, thereby a fixed amount of the sample liquid is transferred to the receiving cavity and an amount of the sample liquid to be discharged into the protective cap is limited to just a minute amount in the guide section. a protective cap that is provided outside the inlet and holds sample liquid scattered from the guide section due to the centrifugal force; and wherein the sample liquid held in the capillary cavity is configured to be broken due to the centrifugal force at the position of the bent section, thereby a fixed amount of the sample liquid is transferred to the receiving cavity and an amount of the sample liquid to be discharged into the protective cap is limited to just a minute amount in the guide section.