  The relativistic harmonic oscillator (RHO) model of hadrons is used to study
quark stars. The mass-radius relationship is obtained and compared with bag
model of quark star, using Tolman-Oppenheimer-Volkoff equation. In this model,
the outward degenerate pressure due to discrete Landau levels and Landau
degeneracy balances the inward gravitational pressure. Where as in bag model
the degenerate pressure is due to the standard continuum levels which balances
the combined inward pressure due to gravitation and bag pressure. So in RHO
model, the confinement effect is included in the degenerate pressure. We found
a qualitative similarity, but quantitative differences in mass-radius
relationship of quark stars in these two models. Masses and radii are
relatively larger and the central energy densities, required for stable quark
stars, are lower in RHO model than that of bag model.
