Abstract: A non-heat treated steel for hot forging and for a connecting rod, containing, in mass percent: 0.3 to 0.8% of C; 0.1 to 2.0% of Si; 0.5 to 1.5% of Mn; 0.01 to 0.15% of P; 1.0% or less of Cr; 0.4% or less of V; 0.05% or less of Al; 0.005 to 0.03% of N; and the balance Fe and inevitable impurities. The non-heat treated steel has a value E of not larger than 150, the value E being calculated from the following equation: E=2804?1549×Ceq?8862×P?23.4×H where H is a value of a Rockwell hardness of the connecting rod made of the non-heat treated steel; P is a phosphorus content (%) in the connecting rod; and Ceq is a value of a carbon equivalent.