An ethylene-based polymer comprising ethylene and at least one addition polymerizable monomer containing a vinyl compound (A) described below, wherein the ethylene-based polymer has a melting temperature (Tm) of 119 ° C. or lower and, the melt index MI (g/10 minutes) of the ethylene-based polymer and the molar content “m” (mole %) of the vinyl compound (A) satisfy the following formula (1): Vinyl compound (A): a vinyl compound represented by the structural formula CH2═CH—R containing a saturated hydrocarbon group R wherein the substituent R has a steric parameter Es of not less than −2.77 and not more than −1.64 and the substituent R has a steric parameter B1 of not less than 1.53 and not more than 2.90: 0.01≧MI≦18+m1.4  (1)