A proton magnetic relaxation study on poly-L-asparagine in the solid state has been carried out in the temperature range 10 K to 400 K at three different frequencies, 60,30 and 18 MHz. The temperature dependence curve of spin-lattice relaxation times exhibits a single minimum typical of dipolar relaxation. The depth of the minimum predicts the presence of some extra NH3+ groups in the poly-peptide. Activation parameters characterizing the molecular dynamics have been determined.