A glass that does not contain BaO, has good chemical durability and hydrolysis resistance, and can maintain excellent chemical durability and hydrolysis resistance even after various heat treatments during container processing. Borosilicate glass for containers is provided. It contains SiO2, Al2O3, B2O3, R2O (R is one or more selected from Li, Na and K) as essential components, and the content of CaO is from 0 to less than 0.5 mol%, (Na2O + K2O + Li2O-Al2O3) / B2O3 Is 0.315 to 0.350 in molar ratio, and BaO is not substantially contained.ＢａＯを含有しないガラスであって、化学的耐久性や加水分解抵抗性が良好な、且つ容器加工時の種々の熱処理後も優れた化学的耐久性や加水分解抵抗性を維持することができる医薬容器用ホウケイ酸ガラスを提供する。ＳｉＯ２、Ａｌ２Ｏ３、Ｂ２Ｏ３、Ｒ２Ｏ（ＲはＬｉ、Ｎａ及びＫから選ばれる１種類以上）を必須成分として含むとともに、ＣａＯの含有量が０～０．５モル％未満、（Ｎａ２Ｏ＋Ｋ２Ｏ＋Ｌｉ２Ｏ－Ａｌ２Ｏ３）／Ｂ２Ｏ３の値がモル比で０．３１５～０．３５０、ＢａＯを実質的に含まないことを特徴とする。
