The invention provides a tunnel bottom plate lining concrete temperature crack control anti-cracking K value design method. The method comprises the following steps of 1, collecting the data for tunnel bottom plate lining concrete temperature crack control design calculation; step 2, analyzing and determining a temperature control anti-cracking target and an anti-cracking safety coefficient allowable value K; step 3, designing a temperature control anti-cracking measure scheme, which comprises the following steps of step 3-1, analyzing a variable, and formulating a plurality of lining concretetemperature control anti-cracking construction measure schemes; step 3-2, calculating the minimum anti-cracking safety factor Kmin of each scheme in the lining concrete construction period by adopting a formula; and step 3-3, under the condition that Kmin is greater than or equal to K, optimally selecting a measure scheme for construction application according to a simple, practical and economicprinciple. According to the method, the temperature control anti-cracking scheme design can be carried out in the design stage, and the method can be used for optimizing and improving the constructiontemperature control measures in real time to achieve the temperature control target for finding problems and changing construction technologies, conditions and the like in the pouring construction process.