Four novel cationic gemini surfactants with the same hydrocarbon chain lengths but different spacers have been investigated in this article. After these cationic gemini surfactants have been synthesized, their structures have been characterized by appropriate spectroscopic methods. By determining their Krafft temperatures, the effects of spacer type and structure on Krafft temperature have been examined. Micellization behaviors of the cationic gemini surfactants have been researched at temperatures above the determined Krafft temperatures. Critical micelle concentration (cmc), counterion binding degree (beta), and counterion dissociation degree (alpha) and standard enthalpy change (Delta H degrees(mic)), standard Gibbs free energy change (Delta G degrees(mic)), and standard entropy change (Delta S degrees(mic)) of micellization of cationic gemini surfactants have been calculated. The solubilization capabilities of these surfactants have been evaluated according to the molar solubilization ratio (MSR). Additionally, the emulsification powers have been measured.