The performance of adding 0–3 wt% B2O3-CuO as a sintering aid to lower the sintering temperature of La0.5Sr0.5Co0.96Ni0.04O3-δ (LSCN) was investigated through solid-state reaction method. Results of linear shrinkage curve, bulk density, and microstructure indicated that BCu addition could promote the sintering process and enhance the densification of LSCN ceramics. With the increase of BCu content, low absolute value of TCR could be achieved, while the conductivity was deteriorated obviously. For LSCN ceramics sintered at 950 °C, the bulk density, conductivity, and TCR were worse than those sintered at higher temperatures. Consequently, the BCu-doped LSCN ceramics might not suitable for the application in the field of LTCC.