In this study, wall greening with vines was constructed using a simple net on a south wall, and the water consumption of the plants was evaluated. A model to estimate the water requirement for wall greening was proposed in which weather conditions and plant growth were considered as explanatory variables. From August 20, 2011 to October 2, 2011, the mean daily water consumption was 18.4 mm, the estimated total water consumption was 1.8 m³ and the mean leaf area per unit of ground (LAI_g) was 11.0. We defined the ratio of water consumption to the maximum value as the standard ratio of water consumption, and estimated the daily standard water consumption rate with our model that uses several climatological factors and LAI_g as explanatory variables. The mean absolute error for the estimation was 6.1 %, suggesting that the water consumption of the wall greening could be evaluated quantitatively through investigation of the water balance of plants.