Solid solutions of LixNa1-xNiO2 Were synthesized and their structures were determined by Rietveld analysis using time-of-flight (TOF) neutron diffraction data. Three phases Were observed: monoclinic (C2/m) phase With x = 0.00, rhombohedral(l) (R m) phase with 0.13 < x < 0.15, rhombohedral(II) (R (3) over barm) phase with 0.70 < x < 1.00. Rietveld analysis of the rhombohedral(l) phase indicated no Ni disordering at the Li/Na (3a) site, and the disappearance of the cooperative Jahn-Teller ordering corresponds to the distance changes between the adjacent Ni layers, Magnetic properties were also measured for these phases.