The giant magneto-impedance (GMI) effect and thermal properties of the Co67.5Fe4.5Ni3Si10B15 amorphous wires, which were prepared by the in-rotating water spinning technique and annealed by passing through a direct current with a tensile stress in N2 atmosphere were investigated. After annealing in N2, the amorphous wire sample exhibits preferable brightness, soft magnetic properties and giant magneto-impedance effect. When the measurement was carried out with an exciting power of 6 dBm and an exciting frequency of 70 MHz, the samples were characterized with the largest impedance change of 125% and the biggest sensitivity of 3.92%/A·m-1. The Co67.5Fe4.5Ni3Si10B15 amorphous wires have the excellent thermal stability in the temperature range of 233-353 K, which makes this kind of amorphous wires promising materials in magnetic sensor application fields.