The 7(1)Pi(g) Rydberg state of Na-2 correlating with the separated atom limit Na(3s) + Na(5p) has been observed using high-resolution cw optical-optical double resonance spectroscopy. A total of 104 identified rovibrational levels in the range v = 0-12 and 11 <= J <= 44 have been assigned to the 7(1)Pi(g) state. Dunham coefficients were determined, and the Rydberg-Klein-Rees potential curve in the range of R = 2.99-4.66 A was derived for the 7(1)Pi(g) state using the observed quantum levels. The important molecular properties are the potential minimum T-e = 36 633.00(23) cm(-1) at R-e = 3.6313(29) angstrom, omega(e) = 115.75(13) cm(-1), and B-e = 0.11122(17) cm(-1). A detailed discussion of this investigation of the 7(1)Pi(g) state is provided.