Disclosed is a small-size receiver that exhibits high sensitivity when used with a plurality of frequencies or a plurality of radio communication systems. To provide a small-size, high-sensitivity, direct conversion receiver for use with a plurality of frequencies or a plurality of radio communication systems, the present invention has a high-frequency-input signal path for a low-noise amplifier optimized for use with various frequencies or radio communication systems. The high-frequency-input signal path includes at least one band-pass filter and its input and output matching circuits. A low-loss switching means is used to connect an optimum high-frequency-input signal path to the low-noise amplifier in accordance with a selected operation mode.