Abstract: Applying some properties of special functions, this paper analysis fully the properties of F distribution density function and points out the relations between this density function and its parameter.
This paper mainly studies the effects of change of the second parameter to density function, proves that the maximum of F(m, n) distribution density function becomes more and more big when n is increasing, also points out the varying regularities of intersection points of F(m, n) distribution density curve and some fixed density curve when n is varying.