An electrode material for a lithium ion battery comprising: an active material represented by LiMPO 4 (M is at least one selected from the group consisting of Fe, Mn, Co, Ni, Zn, Al, Ga, Mg, and Ca), wherein an oil absorption amount for which diethyl carbonate is used (DEC oil absorption amount) is 50 cc/100 g or more and 80 cc/100 g or less, and a ratio (DEC/NMP) of the DEC oil absorption amount to an oil absorption amount for which N-methyl-2-pyrrolidinone is used (NMP oil absorption amount) is 1.3 or more and 1.8 or less, wherein the DEC oil absorption amount is measured using a method according to JIS K5101-13-1 (refined linseed oil method) by changing linseed oil to DEC and the NMP oil absorption amount is measured using a method according to JIS K5101-13-1 (refined linseed oil method) by changing linseed oil to NMP, the active material represented by LiMPO 4 (M is at least one selected from the group consisting of Fe, Mn, Co, Ni, Zn, Al, Ga, Mg, and Ca) is an active material represented by LiFe x Mn 1-w-x-y-z Mg y Ca z A w PO 4 (A is at least one selected from the group consisting of Co, Ni, Zn, Al, and Ga, 0.001≤w≤0.02, 0.05≤x≤0.35, 0.01≤y≤0.10, 0.0001≤z≤0.001), the active material is coated with a pyrolytic carbonaceous film, and the average secondary particle diameter of agglomerated particles formed by the agglomeration of a plurality of primary particles of the active material coated with the pyrolytic carbonaceous film is 0.5 μm or more and 30 μm or less, wherein the average secondary particle diameter is a volume-average particle diameter and the average secondary particle diameter of the agglomerated particles is measured using a laser diffraction and scattering particle size distribution measurement instrument. an active material represented by LiMPO 4 (M is at least one selected from the group consisting of Fe, Mn, Co, Ni, Zn, Al, Ga, Mg, and Ca), wherein an oil absorption amount for which diethyl carbonate is used (DEC oil absorption amount) is 50 cc/100 g or more and 80 cc/100 g or less, and a ratio (DEC/NMP) of the DEC oil absorption amount to an oil absorption amount for which N-methyl-2-pyrrolidinone is used (NMP oil absorption amount) is 1.3 or more and 1.8 or less, wherein the DEC oil absorption amount is measured using a method according to JIS K5101-13-1 (refined linseed oil method) by changing linseed oil to DEC and the NMP oil absorption amount is measured using a method according to JIS K5101-13-1 (refined linseed oil method) by changing linseed oil to NMP, the active material represented by LiMPO 4 (M is at least one selected from the group consisting of Fe, Mn, Co, Ni, Zn, Al, Ga, Mg, and Ca) is an active material represented by LiFe x Mn 1-w-x-y-z Mg y Ca z A w PO 4 (A is at least one selected from the group consisting of Co, Ni, Zn, Al, and Ga, 0.001≤w≤0.02, 0.05≤x≤0.35, 0.01≤y≤0.10, 0.0001≤z≤0.001), the active material is coated with a pyrolytic carbonaceous film, and the average secondary particle diameter of agglomerated particles formed by the agglomeration of a plurality of primary particles of the active material coated with the pyrolytic carbonaceous film is 0.5 μm or more and 30 μm or less, wherein the average secondary particle diameter is a volume-average particle diameter and the average secondary particle diameter of the agglomerated particles is measured using a laser diffraction and scattering particle size distribution measurement instrument.