Crystal structure of arcylamide at -150 degrees C nas studied to understand the role of the crystal structure on the reaction mechanism of radiation-induced polymerization in the solid-state. Acrylamide crystallizes in the monoclinic unit cell with the unit fell parameters as; a=828.0(2) pm, b=578.0(4) pm, c=974.9(2) pm, beta=119.62(4)degrees, space group =P 2(1)/c, Z=4 molecules/unit cell, d(x) = 1.165 g/cm(3). From the results of the structural data a polymerization mechanism in the solid-state is suggested. The radiation damage in single crystal of acrylamide was also investigated in detail. The result showed the formation of the amorphous polymer, that phase separated from the crystalline monomer. The post polymerization proceed at the interface of poly mer-monomer up to 100% conversion.