Polarization reversal and internal electric field were studied for the aromatic polyamides of m-xylylenediamine (MXD) with linear aliphatic dicarboxylic acids in which the number of methylene groups is in the range of 4-10. Polarization reversal was measured for all MXD polyamides at room temperature and at a temperature just above the glass transition temperature (T-g). Large polarization was measured for the polyamides with odd numbers of methylene groups in a dicarboxylic acid unit poled at temperatures above T-g. Internal electric field was measured from the electrochromic spectrum shift and broadening of the probe molecule of 4-(dimethylamino)-4’-nitrostilbene in the polyamides with even numbers of methylene groups in a dicarboxylic acid unit. Large internal electric field was measured for the samples in which the remanent polarization measured from the polarization reversal is small. The large internal electric field is mainly ascribed to the space charges created by the injected charges. Upon thermal annealing, the small depression of the internal electric field was measured in the vicinity of T,, but it is stable until its significant depression occurs around the cold crystallization temperature of polyamides. Thermally stimulated discharge current profiles gave the broad peaks in the same temperature regions where the large depression of internal electric held occurred. These results imply the release of injected charges from the sample film.