A method for dispensing a sample solution and a reagent into a container in a chemical analyser includes a first step of dispensing a reagent into a container, a second step of dispensing a sample solution into the container after the first step, and a third step of dispensing the reagent into the container after the second step. A dilution cup includes an inner face where a diameter of a horizontal section increases on at least one position from a bottom to a top, an opening portion surrounding an opening, where a sample solution is dispensed, located on or near the top, a reagent aperture portion surrounding an aperture where a reagent is dispensed such that the sample solution and the reagent create an upswing spiral flow, and a drain aperture portion surrounding a drain aperture, where a mixed solution of the sample solution and the reagent is discharged, located on or near the bottom.