A sample analyzer prepares a measurement sample from a blood sample or a body fluid sample which differs from the blood sample; measures the prepared measurement sample; obtains characteristic information representing characteristics of the components in the measurement sample; sets either a blood measurement mode for measuring the blood sample, or a body fluid measurement mode for measuring the body fluid sample as an operating mode; and measures the measurement sample prepared from the blood sample by executing operations in the blood measurement mode when the blood measurement mode has been set, and measuring the measurement sample prepared from the body fluid sample by executing operations in the body fluid measurement mode that differs from the operations in the blood measurement mode when the body fluid measurement mode has been set, is disclosed. A computer program product is also disclosed.