Due to the inherent simplicity of the graphene tubule systems, it is expected that these systems will become model systems for the calculation of the mechanical and electronic properties of idealized carbon fibers. In this paper the collective electronic excitations on graphene tubules are discussed. The frequencies of the plasmons on graphene tubules are calculated using an empirical infinitely thin cylindrical-shell model within the framework of a two-fluid hydrodynamic description. There are two parameters involved in our calculation which are calibrated on graphite. The variations of plasmon frequencies and oscillator strength with the size of tube and longitudinal plasmon wavelength are discussed. \textcopyright{} 1996 The American Physical Society.