This paper investigates Hölder’s inequality under the condition of
r
-conjugate exponents in the sense that
∑
k
=
1
s
1
/
p
k
=
1
/
r
. Successively, we have, under
r
-conjugate exponents relative to the
L
p
-norm, investigated generalized Hölder’s inequality, the interpolation of Hölder’s inequality, and generalized
s
-order Hölder’s inequality which is an expansion of the known Hölder’s inequality.