MicroRNAs are provided for evaluating the physiological and/or pathological condition of a subject; and a kit thereof is provided for evaluating the physiological and/or pathological condition of a subject, wherein the kit contains the tools for determining all detectable microRNAs that stably existing in the serum/plasma of a subject; and a biochip for evaluating the physiological and/or pathological condition of a subject, wherein the biochip contains the components for determining all detectable microRNAs stably existing in the serum/plasma of a subject. The aforementioned combination, method, kit and biochip can be used for diagnosis as well as differentially diagnosis of diseases including various tumors.