Polyethylene resin composition, and pipe material, pipe, and joint including the composition

Disclosed is a polyethylene resin composition which includes: a base material mainly including a polyethylene; and an additive, in which the additive includes a nonpolar substance that is a liquid atroom temperature, and a proportion of the additive is 0.1 to 10 parts by mass to the polyethylene of 100 parts by mass. Thus, the polyethylene resin composition can be provided which resists brittle fracture/cracking and stress cracking caused by stress concentration on, if any, invisible minute defects in the composition and which offers sufficient elongation. 本发明提供种聚乙烯树脂组合物以及含有其的管道材料、管道和接头，防止作为聚乙烯所具有的本质性缺点的脆性破损开裂和应力龟裂。聚乙烯树脂组合物含有以聚乙烯为主要成分的基材和添加剂，添加剂含有室温下为液体的非极性物质，添加剂的比例是相对于100质量份聚乙烯的0.1～10质量份。