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The polycrystalline LiCo0.9957Fe0.01PO4 was synthesized by solid-state reaction method. The crystal structure was determined to be orthorhombic with a space group of Pnma by x-ray diffractometer (XRD). The temperature dependence of the magnetization was investigated by superconducting quantum interference device (SQUID) magnetometer. Although LiCo0.9957Fe0.01PO4 showed a typical anti-ferromagnetic behavior at temperatures below TN = 23 K, a rapid increase in magnetization was observed at temperatures below 9 K. The microscopic magnetic properties of LiCo 0.9957Fe0.01PO4 were characterized by 57Fe external field Mössbauer spectroscopy. At temperatures below 9 K, the magnetic hyperfine field (Hhf) showed a rapid increase, while the electric quadrupole splitting (ΔEQ) decreased rapidly. The Hhf and ΔEQ under external field of 4.8 T changed significantly compared to the value without external magnetic field. These are originated from orbital angular moment contribution by spin-orbit coupling at temperatures below 9 K, while orbital angular moment is quenched by the crystalline field due to distorted CoO6(FeO6) asymmetric structure at temperatures above 9 K.