Supporting multimedia traffic is one of the major challenges for the next generation of wireless personal area networks (WPANs). Especially, the IEEE 802.15.4 WPAN standards specify how to guarantee real-time traffic with a type of time division multiple access (TDMA), called the guaranteed time slots (GTS). The GTS mechanism has led many researchers to design techniques aiming to support various real-time applications within the delay jitter. Since the IEEE 802.15.4 standards can operate at low data rate up to 250Kbps, it is limited to guarantee real-time multimedia traffic except voice. The voice traffic has bidirectional characteristics and may go through the multihop in WPAN which can support short-range communications among electronic devices. In this paper, we introduce a virtual cut-through GTS allocation mechanism, namely VC-GTS allocation, for voice traffic in multihop IEEE 802.15.4 systems. The proposed scheme can support bidirectional voice traffic and delivery the traffic t...