Amorphous thin films of Sn(10)Sb(20-x)Bi(x)Se(70) (0 <= x <= 6) system have been prepared by thermal evaporation technique. The optical gap and dc activation energy first increases with the addition of Bi (x = 2) and then decreases sharply with further addition. The photocurrent initially increases with time and then saturates to a constant value for all the samples. The decay portion of photocurrent has two components, fast one followed by a slow decay. Photocurrent (I(ph)) versus light intensity (F) follows the power law I(ph) proportional to F(gamma) and the value of the exponent (gamma) decreases from 0.76 to 0.53 as the Bi concentration varied from x = 0 to 6 in the present system. The photosensitivity of these samples varies from 1.27 to 1.13 as Bi content increases. (C) 2009 Elsevier B.V. All rights reserved.