The xBi(Zn2/3Nb1/3)O3(1x)(K0.5Na0.5)NbO3 (abbreviated as xBZN(1x)KNN) ceramics have been synthesized using the conventional solid-state sintering method. The phase structure, dielectric properties and relaxorlike behavior of the ceramics were investigated. The 0.03BZN0.97KNN ceramics show a broad and stable permittivity maximum near 2000 and lower dielectric loss (5%) at a broad temperature usage range (100 degrees C400 degrees C) and the capacitance variation (C/C150 degrees C) is maintained smaller than +/- 15%. The 0.03BZN0.97KNN ceramics only possess the diffuse phase transition and no frequency dispersion of dielectric permittivity, which indicates that 0.03BZN0.97KNN ceramics is a high temperature relaxorlike ferroelectric ceramics. These results indicate that 0.03BZN0.97KNN ceramics are excellent promising candidates for preparing high-temperature multilayer ceramics capacitors.