A fully developed mixed convection flow between inclined parallel flat plates filled with a porous medium is considered through which there is a constant flow rate and with heat being supplied to the fluid by the same uniform heat flux on each plate. The equations governing this flow are made non-dimensional and are seen to depend on two dimensionless parameters, a mixed convection parameter lambda and the P,clet number Pe, as well as the inclination gamma of the plates to the horizontal. The velocity and temperature profiles are obtained in terms of lambda, Pe and gamma when the channel is inclined in an upwards direction as well as for horizontal channels. The limiting cases of small and large lambda and small Pe are considered with boundary-layer structures being seen to develop on the plates for large values of lambda.