We present the results of two studies of the inner Galaxy : on the one hand, a maximum likelihood fitting method using the Besançon model of Galaxy to constrain the density laws of the outer bulge and the holed disc; on the other hand, the comparison of Besançon simulations with infrared data on fields near longitude 20 27 degrees to verify the existence of a long and thin in-plane bar. These two parallel studies seem to show the co-existence of a structure (the bar) in addition with a very oblate outer bulge.