There are herein disclosed a branched ethylenic macromonomer which can function as a comonomer to provide a copolymer having excellent molding and working properties and which can be hydrogenated to provide a hydrogenated product as a wax useful in various uses, a copolymer having the excellent molding and working properties obtainable by using this macromonomer as a comonomer, and a branched ethylenic polymer having a low-molecular weight obtainable by hydrogenating the macromonomer. The branched ethylenic macromonomer of the present invention is derivable from ethylene singly or derivable from ethylene and another olefin, (a) a molar ratio of a terminal methyl group/a vinyl group in the macromonomer being in the range of 1 to 100, the macromonomer having a branch other than the branch directly derived from the other olefin, (b) a ratio of vinyl groups to the total unsaturated groups in the macromonomer being 70 mol % or more, (c) a weight-average molecular weight of the macromonomer in terms of a polyethylene measured by a GPC being in the range of 100 to 20,000.