Dynamic light scattering (DLS) was used to study diffusion of Linear sodium poly(styrenesulfonate) (NaPSS), with molecular weights ranging from 35 000 to 1 200 000, in poly(acrylamide) (PA) gels made by copolymerizing acrylamide and N,N’-methylenebis(acrylamide) (BIS) in aqueous solvents of high and low ionic strengths. Laplace inversion of the correlation functions shows that for the gels swollen in solvents with a high effective ionic strength two distinct, well-separated bands appear in distributions of diffusion coefficients, corresponding to the collective diffusion mode of the gel, D-g, and the tracer diffusion of the probe polymer, D-p. The scaling laws D-p similar to M(p)(-2) and D-p similar to M(p)(-2.1), where M(p) is the molecular weight of probe NaPSS polymer, were found for 11 and 18 wt% gels, respectively. These results are close to the reptation prediction for the self-diffusion of neutral flexible polymers in gels. The dependence of D-p and D-g on the concentration of the gel, c(g) was also measured, and scaling relationships were observed with D-p similar to c(g)(-2.5) and D-g similar to C-g(0.67). The dependence of D-p on the concentration of the probe polymer c(p) did not obey a power law but showed behavior similar to that predicted by random phase approximation theory for semidilute solutions of polymer mixtures. In the case of gels swollen in deionized water, three different bands were observed where the slowest one was on the long time measurement limit.