This paper investigates the use of aluminum gallam to generate polyselenides by the reduction of elementary selenium, selenides and selenates in aqueous alkaline solutions. The results show that the reduction of SeO3 2- on aluminum gallam generated selenides and polyselenides. The oxidation of Sen 2- up to elementary selenium by oxygen in alkaline solutions proceeds consistently through intermediate stages of formation of polyselenides Sen 2-. Maximum absorption of the polyselenide solutions was recorded in the range of 240-500 nm.