  Warm inflation is extended from the canonical field to the noncanonical field
with a general Lagrangian density having coupling form of kinetic and potential
terms. We develop the motion equation of the noncanonical inflaton field, and
notice the motion equation has an annoying coupling term
$\mathcal{L}_{X\varphi}\dot\varphi^2$, which makes the inflation difficult to
solve. It is found that a special field redefinition exists, making the motion
equation of inflaton uncoupled. Then we can solve inflation in the special
field representation for convenience. The relation of field redefinition
between the special uncoupled field and general noncanonical field is obtained.
The motion equations and slow roll approximations of noncanonical warm
inflation in the special field representation are developed. Then we give two
examples to show how to translate a general noncanonical Lagrangian density in
the coupled $\varphi$ representation, to the uncoupled $\phi$ representation.
Finally, the cosmological perturbations generated by the new kind of warm
inflation is calculated.
