Working medium heating device of gas turbine solar power generation system

The invention discloses a working medium heating device of a gas turbine solar power generation system. The device comprises a cold air passageway (5), a heat collecting cavity (7) and a hot air channel (26) which are communicated sequentially; the hot air channel (26) is formed by connecting an inner shell (28) at the front side and a heat compensation section (13) at the rear side; and the device also comprises a combustor (20) which heats primary heating air (27) in the heat compensation section (13) when the solar energy is insufficient, and the combustor (20) is arranged at the heat compensation section (13). By adopting the working medium heating device of the structure, the solar energy and other gaseous fuel materials can be combined to be utilized according to the direct radiation condition of solar energy, the primary heating air of the heat compensation section is subjected to fuel combustion compensation when the solar energy is insufficient; and because the combustor is simple in structure and lower in manufacturing cost, thus on the premise of low cost, the working medium heating device can be used for maintaining the stability and adjustability in outputting electricity externally by the power generation system when the solar energy is insufficient.