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We address the feasibility of imaging geometric and orbital structure of a polyatomic molecule on an attosecond time-scale using the laser induced electron diffraction (LIED) technique. We present numerical results for the highest molecular orbitals of the CO2 molecule excited by a near infrared few-cycle laser pulse. The molecular geometry (bond-lengths) is determined within 3% of accuracy from a diffraction pattern which also reflects the nodal properties of the initial molecular orbital. Robustness of the structure determination is discussed with respect to vibrational and rotational motions with a complete interpretation of the laser-induced mechanisms.With the development of attosecond laser sources [1], ultrafast molecular imaging has become a major research topic in modern physics. On one hand, attosecond laser pulses are directly used to image dynamical processes in schemes such as the attosecond pump-probe spectroscopic mapping of molecular motions [2] or the interferometric real-time observation of electronic motions [3]. On the other hand, a number of schemes have been proposed to image molecular structure, which are all based on the rescattering mechanism [4]. This phenomenon consists of the tunnel ionization of an electron followed by its acceleration and its return by the field, to end with its recollision with the molecular ionic core. The possible outcomes of this mechanism are all relevant to molecular imaging. The elastic scattering of the returning electron with the ion core defines the LIED [5,6], which can be compared with ultrafast electron diffraction using an external electron source [7]. Inelastic scattering of the returning electron may be accompanied by electronic excitation of the parent ion, its further ionization or the emission of high-energy radiation. This last process, high-harmonic generation (HHG), has been used directly as a probe or indirectly to unveil orbital and molecular structure, and even to image rotational and vibrational motions [8].We wish to assess the feasibility of imaging polyatomic molecular structure, e.g., measuring its geometrical parameters, such as bond-lengths and/or bond-angles), on an attosecond time-scale using the LIED technique. We show how a diffraction pattern constructed from measurable photo-electron momentum distribution encodes informations on the electronic orbital nodal properties but also on the geometry of the nuclei. We assess the robustness of this two-fold structure determination procedure with respect to inevitable uncertainties about the alignment of the molecule relative to the field polarization direction, its bond lengths and angles. We consider a relatively simple model of the CO 2 molecule, the choice of which being motivated by different considerations: Being linear in its symmetric equilibrium geometry, it is simple enough, in particular with respect to its alignment properties, and yet with three nuclei, it has enough internal degrees of freedom to make its molecular structure determination challenging.To concentrate on the pr...