A non-crosslinked polyethylene foam is disclosed, which is obtained by foaming a polyethylene resin satisfying the following requirements (a) to (d): (a) a density is 890-980 kg/m3; (b) the number of long chain branches having 6 or more carbon atoms is 0.01-3 per 1,000 carbon atoms; (c) a melt tension (mN) measured at 190° C. (MS190) and MFR (melt flow rate: g/10 min, 190° C.) under a load of 2.16 kg are satisfied with the following formula (1): MS190>22×MFR−088   (1) and a melt tension (mN) measured at 160° C. (MS160) and MFR (melt flow rate: g/10 min, 190° C.) under a load of 2.16 kg are satisfied with the following formula (2): MS160>110−110×log (MFR)   (2) (d) an endothermic curve obtained in temperature-rise measurement by a differential scanning calorimeter shows one peak.