Titled homologous series: n-Butyl-p-(p/-n-alkoxy cinnamoyloxy) cinnamates is synthesized and studied with a view to understand the relation between mesogenic properties of substances and their dependence on molecular structure. Methyl to pentyl homologues are nonmesogenic, while, hexyl, octyl, decyl, dodecyl, tetradecyl and hexadecyl homologues are enantiotropically mesogenic with exhibition of only nematogenic character. Smectogeni character is totally absent. Phase diagram is obtained by plotting a graph using number of carbon atoms in n-alkyl chain of left n-alkoxy terminal end group,versus transition temperatures as determined from polarizing microscope with heating stage. Solid-isotropic or solid-nematic transition curve shows descending tendency without following zigzag path, irregularly up to hexyl / octyl homologue and than it follows zigzag path of rising and falling as series is ascended. Nematic – isotropic transition curve behaves in normal manner without showing up of odd-even effect. Average thermal stability is relatively higher than the structurally similar homologous series selected for comparative study. Textures of the homologues are of threaded type. Analytical data support the structures of the molecules.