Li-doped KTaO3, K(1-x)Li x TaO3 (KTL) has been reported to be a relaxor with an isovalent substitution of Li+ for K+. For confirming the idea, we performed second-harmonic generation microscopic observations, X-ray diffraction experiments and dielectric measurements of KTL with the critical concentration of Li (x = 3%). These reveal that an intermediate phase exists between 2 characteristic temperatures, Td and Tp. The former corresponds to an elastic change accompanying small deformation and the latter to a dipolar change of the crystal. It is highly probable that the polar-nano regions appear below Td and transformed into ferroelectric domains at Tp. The present experiments support that KTL is a real relaxor.