The lanthanium modified lead titanite(PLT) nanocrystals were prepared by sol gel method. The effects of calcination temperature on the crystal size, lattice parameters and c/a ratios of the products have been investigated by XRD technique. The relation between the crystal size and c/a ratio in terms of lanthanium contents in the modified titanite has been discussed. The effects of calcination temperature on the crystal size, lattice parameters and c / a ratios of the products have been investigated by XRD technique. The relation between the crystal size and c / a ratio in terms of lanthanium contents in the modified titanite has been discussed.