Abstract: The present study was carried out to gain some knowledge on length-weight relationship parameters and difference between the biometric characters of little tuna (Euthynnus alletteratus) from two regions in the Tunisian coastline. The knowledge of biometric characters has numerous practical applications in fishery biology. A total of 178 Euthynnus alletteratus individuals were sampled between January 2008 and December 2009, from two areas of Tunisia, one in the North (Teboulbah) and another one in the South (Zarzis) using multivariate fishing gear. Some fifteen morphometric and six meristic characters were examined for geographic variation. Morphometric characteristics were calculated as a percentage of the fork length. Morphological variation among the E. alletteratus collected showed significant differences (p<0.05) between Teboulbah and Zarzis specimens in maximum body height (H), Head Length (HL) and snout length (SnL). No significant differences were observed in the meristic characters of the two localities tested. Regression coefficients were estimated by using the logarithms of the fork length and the total weight. The length-weight relationships were determined for combined sexes as W = 0.031 FL2.815 for Teboulbah and W = 0.022 FL2.906 for Zarzis. The b-value obtained for Teboulbah and Zarzis indicate that the fish follows the cube law and its growth is negative allometry.