The present invention provides a mobile broadband device, and relates to the field of communications technologies. The mobile broadband device includes a casing, a Printed Circuit Board Assembly (PCBA), and an antenna. The antenna and the PCBA are both set in the casing, and the PCBA can be slidably pulled out or retracted back along the casing. The antenna is fixedly set on an inner side of the casing and forms a hollow space for accommodating the retracted PCBA, there is a contact point set on the antenna, and the contact point is electrically connected to a feed point of the PCBA. With the mobile broadband device, the antenna does not individually occupy part of space in the casing without affecting the performance of the antenna; therefore, the volume and length of the mobile broadband device are effectively reduced, and the portability of the mobile broadband device is effectively improved.