The electronic spectra and energy levels of Ho3+ in Cs2NaYF6 were studied on basis of rare earth (RE) spectrum, quantum mechanics and crystal field theory. Detailed analysis on electronic absorption spectra at temperatures down to 10 K in the range of 4 600-24 000 cm-1 was carried out. The transitions, with zero phonon lines (ZPL) and abundant vibronic sidebands, from ground states to different excited states such as 5IJ(J=7,6,5,4),5FS(S=5,4,3),5GP(P=6,5) and 3K8 were clearly observed. All the transitions have been assigned and 50 experimental crystal field levels have been obtained. The dataset has been investigated by standard f-shell program, which gave out the calculated energy levels and the corresponding empirical Hamiltonian parameters. The comparison of the energy levels and Hamiltonian parameters was made with that of Cs2NaYCl6∶Ho3+ as well.