Mixing cyclic pentagonal pillar[5]quinone with cyclic hexagonal pillar[6]arene in a 12:20 molar feed ratio resulted in spontaneous production of vesicles, while assembly of pillar[6]arene and pillar[5]quinone alone produced hexagonal disks and wires, respectively. Incorporation of pentagonal pillar[5]quinone rings into hexagonal pillar[6]arene sheets gave curvature and contributed to the formation of vesicles. Conventional vesicles are generally synthesized by assembly of amphiphilic molecules containing hydrophobic and hydrophilic parts. Therefore, the co-assembly of pentagonal and hexagonal molecules to obtain spherical vesicles demonstrated in this study is a new concept based on geometric design.