We will investigate the superstability of the (hyperbolic) trigonometric functional equation from the following functional equations: f ( x + y ) ± g ( x − y ) = λ f ( x ) g ( y ) , f ( x + y ) ± g ( x − y ) = λ g ( x ) f ( y ) , f ( x + y ) ± g ( x − y ) = λ f ( x ) f ( y ) , f ( x + y ) ± g ( x − y ) = λ g ( x ) g ( y ) , which can be considered the mixed functional equations of the sine function and cosine function, of the hyperbolic sine function and hyperbolic cosine function, and of the exponential functions, respectively.