A part of Toulouse’s underground line B has been excavated by a 7.8 meters diameter earth-pressure balance machine. A comprehensive monitoring section has been installed in the Compans garden at a point where the tunnel cover is 12.8-meter and is running through overconsolidated clayey molasses underlying a 6.8 meters layer of made ground and gravels. The monitoring devices give full information on the ground movements above the tunnel and on deformations of the tunnel lining. Vertical movements are measured by 5 multipoint borehole extensometers with automatic data acquisition (every 5 seconds when the TBM crosses the monitoring section). At the end of each excavation phase, a high precision levelling of the borehole extensometer heads is performed in order to determine the total vertical displacements. Horizontal movements are measured by 3 inclinometers, one in the axis of the tunnel and the others on its sides, 2.3 meters away from the tunnel extrados. One of these inclinometers is 42 m long, i.e. 21.8 m below the level of the tunnel invert. The induced horizontal strains at ground level are measured by an invar thread in both longitudinal and transverse directions. Measurements show a specific behaviour of the soil due to its overconsolidated character (K0 greater than 1.5): even though the magnitude of the displacements is limited to a few millimeters, horizontal convergent movements are observed at the level of the tunnel axis while 3 to 4 times smaller heave is measured at ground surface (associated with horizontal extensions). Excavation parameters are automatically recorded and give information on the variation of the torque on the cutting wheel, the advancement rate, the confining pressure, the injection of annular void between soil and the concrete tunnel lining… This paper presents the results of the different monitoring devices and the possible correlations with the tunnel excavation parameters recorded by the TBM.