Abstract: A handheld loudspeaker device, comprising: a handheld base, a first port and a second port, a first sound guidance tube, and a second sound guidance tube. A front end of said handheld base is provided with a receiving space to place said mobile phone. Said first port and said second port are each placed on one side of said receiving space, so that said first port is connected to a loudspeaker of said mobile phone to transmit sound, and said second port is connected to a microphone to receive voice. When a user activates loudspeaker function of said mobile phone, stereo sound can be obtained at the loudspeaker slots corresponding to a first horn port and a second horn port. Through said second port, a user can speak to a receiving party at a remote end via the Public Switched Telephone Network (PSTN) and the Internet.