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〈Abstract〉Two polybenzimidazole-derived cationic polymers were synthesized, and their chemical and physical properties were investigated to develop hydroxide ion conducting materials for anion exchange polymer membrane fuel cells (AEMFC). One was poly(methylbenzoimidazoliumiodide) (PBI-E-3.8MI), which was synthesized by N-methylation of polybenzoimidazole having ether oxygen (PBI-E). The other was polybenzoimidaozole having propytrimethylammonium bromide groups (PBI-DB-1.4TAB), which was synthesized by introduction of propyltrimethylammonium groups on the imidazole nitrogen. PBI-E-3.8MI showed high thermal stability but low alkaline resistance with low anion exchange ability. On the other hand, PBI-DB-1.4TAB exhibited moderate thermal stability but high alkaline resistance with high anion exchange ability. PBI-DB-1.4TAB film also showed good ionic conductivity under alkaline conditions along with a good mechanical strength. These results suggested that PBI-DB-1.4TAB can be a good candidate as hydroxide ion conducting materials for AEMFC.