The present invention discloses lithium iron phosphate material for lithium ion power cell and its preparation process, and dissolves the technological problem of raising the discharge power and safety performance. The lithium iron phosphate material is spherical or spheroid composite particle with one base body of lithium iron phosphate and doping and modifying agent and one coating carbon layer. Its preparation process includes wet ball milling the mixture comprising lithium salt, ferric salt, phosphoric acid, doping and modifying agent and dispersant, spraying to pelletize, heating for pre-treatment, maintaining temperature, cooling, pulverizing and shaping. Compared with available technology, the present invention has the features of high crystallization, single structure, average composite particle size of 5-60 microns, specific surface area of 8.0-15.0 sq m / g, bulk density of 1.4-1.7 g / cu cm, high specific capacity, high safety, etc.