In this paper, the theoretical atomic energy level values for configurations 4s2, 4s4p, 4s4d, 4s5s of zinc –like isoelectronic sequence ions from Rh X VI to In XX are calculated with HXR method in Cowan’s computer code. By analysing variation of the differences D E between theoretical and experimental energy level values with Zc (Zc=Z–N+1)along the isoelectronic sequences, we put forward a new fit formula. Using this formula and the FORTRAN programe designed by us, we have made a systematic fit calculation for the energy level values of configuration mentioned above. Some unknown energy levels belonging to the ions (RhXVI –In XX)are predicted by interpolate and extrapolate. Also, the 4s2 –4s4p, 4s4p –4s4d transition wavelengths and the corresponding HXR calculating oscillator strengt