A CardBus PC Card type wireless transmitting/receiving device performs a wireless data transmission/reception operation between a plurality of notebook PCs and an MB-OFDM (Multiband Orthogonal Frequency Division Multiplexing) UWB (Ultra Wide Band) type piconet coordinator. The device includes a wireless 1394 device, built in the notebook PC in the form of a CardBus PC Card, for converting a CardBus PC Card access signal of the notebook PC into an MB-OFDM UWB signal to transmit the converted MB-OFDM UWB signal, and inversely converting a received MB-OFDM UWB signal into a CardBus PC Card access signal of the notebook PC. The device can easily be built in a notebook PC, has a simple structure with a low cost, has a very high wireless transmission speed of 55 to 480 Mbps in comparison to the existing IEEE 802.11b type wireless 1394 bridge device in the form of an external IEEE 1394 adapter, and guarantees the QoS (Quality of Service) using the IEEE802.15.3 type MAC to provide a high-quality service to users.