Most vital-sign transmission systems utilize wireless technology using radio wave. However the radio wave transmission has some problems such as electro-magnetic compatibility. We propose a novel vital-sign telemetry system using NF-IBC (Near-Field Intra-Body Communication) which communicates without radio wave, in order to solve any issues that radio wave transmission has. In previous research, we developed and tested NF-IBC transmitter. In this paper, SS (spread spectrum) technique was applied to NF-IBC to improve the communication reliability. First of all, we changed the condition of the transmission path, and evaluated the error rate of transmitted data. As the next step, we compared and evaluated noise immunity on SS and non-SS NF-IBC. Finally, we tried to transmit ECG data measured on the body. The results from these experiments show that SS NF-IBC has sufficient reliability on basic performance and applicability to ECG transmission.