The majority of studies for laminar free-convection over a vertical isothermal plate with uniform blowing or suction concern gases and air. The existing results for water have been produced assuming a linear relationship between fluid density and temperature and constant viscosity and thermal conductivity. However, it is known that the density-temperature relationship for water is non-linear at low temperatures and viscosity and thermal conductivity are functions of temperature. In this study the problem of laminar free-convection over a vertical isothermal plate with uniform blowing or suction in water has been investigated in the temperature range between 20 and 0degreesC taking into account the temperature-dependence of mu, k and rho. The results are obtained with the numerical solution of the boundary layer equations. The variation of mu, k and rho with temperature has a strong influence on the results.