Compressive properties of fibers made from ionic naphthalene theromotropic polymers (NTPs) were investigated. These (main-chain) thermotropic liquid crystalline polymers (LCPs) are wholly aromatic copolyesters, which contain 1 mol % ionic groups with either monovalent Na ion or divalent Ca ion. The SEM observations of kink band formation on both a single knotted fiber and a deformed fiber under axial compression in a composite suggest enhanced compressive properties for the ionic NTP fibers as compared with nonionic NTP fibers. It is believed that the enhancement of the compressive properties is due to the presence of strong lateral ionic bonds in the ionic NTP fibers, which provide interlinks both between molecules and between supermolecular domains. Tensile strength values of the ionic NTP fibers are slightly higher than those of the nonionic NTP fibers, even though the take-up speed, and thus the molecular orientation, is lower for the ionic NTP than for the nonionic NTP. This reflects the beneficial effect of ionic bonds in enhancing tensile properties.