The present invention provides a nonaqueous electrolyte secondary battery laminated separator which improves a long-term battery characteristic of a nonaqueous electrolyte secondary battery. According to the nonaqueous electrolyte secondary battery laminated separator in accordance with an aspect of the present invention, an absolute value of a difference between (i) a standard deviation of whiteness index in one outermost layer and (ii) a standard deviation of whiteness index of the other outermost layer is greater than 0.01 and is 0.60 or less, and a greater one of the two standard deviation values of whiteness index is 0.06 or more and 0.91 or less.