Accelerated aging test have been carried out on eighteen Panicum maximu Jacq. submitted seed samples, aiming at test standartdization for the species. All seed samples used had presented statistically similar initial germination values. Accelerated aging for 12, 14, 36 and 48 hours at 43 oC +- 0.5 and 100% relative humidity were the treatments used. Statistically different vigor data were recorded among seed samples after the accelerated aging treatments used. However, the 48 hour-period treatment showed to be hazardous to the seeds, causing a market decrease in gemination percentage values. The 12 and 24 hours-period treatments presented contrasting results. On the other hand, the 36 hours-treatment was able to detec vigor differnces among seed samples quite effectivelly and is recommended here to be used in Panicum maximu Jacq.