The dependence of 7Li NMR spectrum in LiKO4 on temperature and crystal orientation has been studied. It is confirmed that there is a structural phase transition at Tc = 195K below which the crystal symmetry is lower than P31c and its unit cell contains at least six molecular formulae. There is no evidence of the existence of an incommensurate phase. At 181K the quadrupole coupling conatant is 38.9 kHz, the asymmetry parameter η = 0.46, and the principal direction z of the electric field gradient makes an angle of 11.6° with the original c axis.