The invention relates to a combined type computer allowing expanded use. The combined type computer comprises an expanding machine and a portable host computer. The portable host computer comprises a CPU chip, a primary memory, a primary hard disk, an integrated sound card, an integrated display card, an integrated network card, a rechargeable battery, a display screen, an internally-arranged loudspeaker box, a first USB interface and a first expanding interface, and a CD-ROM is not arranged. The expanding machine comprises a peripheral power source, a secondary memory, a secondary hard disk, an independent display card, an independent sound card, an independent network card, a CD-ROM, a second USB interface and a second expanding interface, and a CPU chip is not arranged. The portable host computer can be independently used, and is portable, and easy to carry. Functions and performance of the portable host computer can be expanded and enhanced through the expanding machine, and therefore use requirements of users under different environments can be met.