The purpose of this study is to investigate some bulk known regularities for confined fluids and nanofluids. The studied regularities included: the common compression point, common bulk modulus point, bulk modulus - pressure regularity (Tiat- Murnaghan equation) and pressure – temperature Isochores for fluids with Lenard-Jones (12-6) potential in nanoslit and the regularity between viscosity and surface tension for nanofluids. Our results show that the different isotherms of compressibility factor and also bulk modulus of confined fluid intersect each other versus average density of fluid in nanoslit pores, called common compressibility and bulk modulus points. At these points the compressibility and bulk modulus quantities are independent of temperature. Also we have showed that the values of the compressibility factor and bulk modulus increase with temperature for all densities lower than the density of intersection points and decrease with temperature for densities greater than the density of intersection. In addition, the effect some factors such as nanoslit size and fluid – wall interactions evaluated in these regularities. It has been also observed that the common compression and common bulk modulus points still exist for nanoconfined fluids with any size and fluid – wall interactions. It has been also observed that the values of the compressibility factor, bulk modulus and density at intersection points increase with nanoslit size and approaches to its macroscopic values at macroscopic limit. But the effect of wall-fluid attraction on these regularities is different. by variation of the wall-fluid interactions from hard to Lenard – Jones (10-4-3) potential, the values of compressibility factor and density at common compression point decrease while the value of bulk modulus and density at common bulk modulus point increase. We have also studied Tait – Murnaghan equation for nanoconfined fluids. It has been also found that the reduced Bulk Modulus is linear verses lateral pressure for any isotherms. This regularity also exists for Lenard – Jones fluid in nanoslit with any size and fluid – wall interactions. The last studied regularity for confined fluids is the linear regularity between lateral pressure and temperature for any isochores for Lenard – Jones fluid in nanoslit with different size and wall- fluid interactions. In overall, our studied show that these regularities is related to the intrinsic properties of fluids and introduction of wall only changes the thermodynamic states at which the regularities happened. Finally, the regularities between viscosity and surface tension in nanofluids have been examined. These regularities include a linear regularity between ratio of surface tension to viscosity verses root of temperature and also a linear regularity between surface tension logarithm and inverse viscosity.