Piezoelectric properties of (Pb1-5xLax)(Ti0.98Mn0.02)O3(PLT) ceramics at VHF band were studied to examine their applicability as ceramic resonators. With the amount of La substitution in the range of x=0.05 to 0.25 the concentration of Pb-vacancies in the ceramics was gradually increased resulting in improved sinterability and decreased lattice anisotropy. Thickness-longitudinal vibration mode resonators fabricated with 0.3mm thick PLT ceramics showed better piezoelectric characteristics at the 3rd overtone resonant frequency(fr3) of about 24MHz than at the fundamental resonant frequency(fr0) of about 8MHz. When x=0.15 the values of elastic stiffness coefficient(c33) and electromechanical quality factor(Qm) reached maximum values of 2.1$ imes$1011 N/m2 and 3400 respectively while the 3rd harmonic piezoelectric coupling factor(kt) showed a minimum value of 11% Very low temperature coefficients of fr3(<10ppm/$^{circ}C$) were obtained with the PLT ceramic resonators when x=0.1~0.15