This paper reports for the first time the Doppler-free optical-optical tripleresonance(DF-OOTR) excitation fluorescence spectra for a series of Rydberg energy levels in sodium molecules, and the linewidths and lineshifts under the variations of temperature and foreign buffer-gas pressure. The results demonstrated that the natural widths(including homogeneuos broadening) of these Rydberg energy levels (n=5～8)are between 60～130 MHz, and mainly depend on the principal quantum number n. All these levels are in red line-shifts with the increase of atomic density (the increase of temperature) or foreign buffer-gas (Ar) pressure, but with different shift rate within 100 MHz/τ.