The growth and the structure of a Xe film physisorbed on a Ag(l 11) substrate have been investigated by means of ellipsometry and extremely low current low-energy electron diffraction (XLEED). Equilibrium between the Xe film and the coexisting three-dimensional Xe gas was maintained throughout the film growth. From a monolayer to a sufficiently thick film, the Xe film has a clear hexagonal structure whose directions of the unit vectors are coincident with those of the substrate. We have made a systematic observation of the change of the Xe-Xe spacing in the process of film growth. The Xe-Xe spacing just after the first layer condensation is a few percent larger than that of the bulk. While the pressure is increased or the temperature is lowered, the Xe-Xe spacing decreases gradually and reaches the bulk value before the second layer condensation. The second layer adatom density has been determined from ellipsometric and XLEED data. It was found that the compression in the first layer precedes the second layer adsorption. Using a simple model, we calculated the densities of the first and the second layer, which are consistent with our experimental results.