纳税亏损是根据所得税法规定计算出来的企业在某一期间的税前亏损。《中华人民共和国企业所得税暂行条例》第１１条规定 :“纳税人发生年度亏损的 ,可以用下一纳税年度的所得弥补 ;下一纳税年度的所得不足弥补的 ,可以逐年延续弥补 ,但是延续弥补的期限最长不得超过五年。”《 Tax losses are calculated based on income tax law of the enterprise during a period of pre-tax losses. Article 11 of the Provisional Regulations on Enterprise Income Tax of the People’s Republic of China stipulates: “Where an annual loss occurs to a taxpayer, it may be used to make up for the income of the following tax year; if the income in the next tax year is insufficient to make up for it, it may be renewed year by year, The maximum period of no more than five years. ”"