The electrical resistivity, ϱ, and temperature derivative of resistivity (d/dT) of polycrystalline NdFe11Ti are investigated. The resistivity exhibits an anomalous behavior at about 160 K and 220 K. These anomalies attributed to spin reorientation phenomena originate from two magnetic phase transition. A modified theoretical model for electrical resistivity, ϱ and dϱ/dT, behavior in the spin reorientation temperature (TSR) region is presented. The results suggest that the average magnetic moment at TSR1 ∼ 160 K is aligned along a cone angle and at TSR2 ∼ 220 K along c-axis. The temperature dependence of ac-susceptibility, χac(T), is presented. The results show the existence of the spin reorientation related to a magnetic phase transition. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)