In this paper, we propose the LEAST-SQUAREs METHOD for computing the positive solution of a m´n fully fuzzy linear system (FFLS) of equations, where m>n, based on Kaman's arithmetic operations on fuzzy numbers that introduced in [18]. First, we consider all elements of coefficient matrix are non-negative or non-positive. Also, we obtain 1-cut of the fuzzy number vector solution of the non-SQUARE FFLS of equations by using pseudoinverse.If 1-cuts vector is non-negative, we solve constrained LEAST SQUAREs problem for computing left and right spreads. Then, in the special case, we consider 0 is belong to the support of some elements of coefficient matrix and solve three overdetermined linear systems and if the solutions of these systems held in non-negative fuzzy solutions then we compute the solution of the non-SQUARE FFLS of equations. Else, we solve constrained LEAST SQUAREs problem for obtaining an approximated non-negative fuzzy solution. Finally, we illustrate the efficiency of the proposed METHOD by solving some numerical examples.