The present invention relates a kit of a standard reagent for analysis of a dialysis fluid consisting of (1) a vial A filled with aqueous solution A comprising an electrolyte component enabling the reaction with carbonate ions to form a precipitate, and (2) a vial B filled with aqueous solution B comprising at least any one of hydrogencarbonate ion and carbonate ion, wherein at least the vial B is a water-shedding resin vial. A standard reagent for analysis of a dialysis fluid wherein a precipitation is prevented for long period of time, a change of the content of hydrogencarbonate ion is controlled, which does not require complicated procedure for preparation, which is easy to handle and which allows a check of a dialysis fluid after preparation at medical site to implement easily and accurately is provided.關於一種透析液分析用的標準試劑套組,係由下列構成之透析液分析用的標準試劑套組:(1)小瓶A,其填充有含有能夠與碳酸根離子反應並形成沉澱之電解質成分的水溶液A液,及(2)小瓶B,其填充有含有碳酸氫根離子與碳酸根離子之至少任一個的水溶液B液,其中,至少小瓶B為撥水性樹脂小瓶,並提供一種透析液分析用的標準試劑,其為能夠在長時間內防止析出沉澱並抑制碳酸氫根離子含量之變化之透析液分析用的標準試劑,其在調製上不須繁雜的步驟,操作簡單,且能夠在醫療現場簡易並正確地進行透析液調製後的檢查。