-This paper will focus on theoretical study of BEC in one dimension with weakly attractive interactions in particular in a symmetric harmonic oscillator potential. In this case, the ground state may not be symmetric state, which is in contrast to a BEC with repulsive interaction. The behaviors of the wave function under the influences of different external trapping potentials usually used in experiments that lead to produced Bose-Einstein condensation in ultra cold gases is analysis. Several values of harmonic trapping potentials are used. These analyses give us the overall view of the region of confinement that the external trapping potentials have employed and the influence of some terms in Gross-Pitaevskii equation.