The influence of grain boundary chemistry and misorientation on the intergranular corrosion of Al-Mg-Si-T6 alloys with trace level of Cu (upto 0.05 wt%) and Zn (upto 0.06 wt%) was investigated. Aim was to simulate effect of trace level Cu and Zn content getting into the Al-Mg-Si alloys during the recyling process. Microstructure of the alloy including grain boundary chemistry was investigated using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and high resolution Transmission Electron Microscopy (TEM and STEM). Grain boundary misorientation was profiled using Electron Backscatter Diffraction (EBSD). IGC susceptibility of the alloys was investigated by exposure to aqueous solution containing 10 ml/L concentrated hydrochloric acid and 30g/L NaCl under different immersion times and electrochemical impedance spectroscopy. Results from IGC attack was correlated with grain boundary chemistry and grain misorientation. Even trace levels of Cu and Zn in the alloys caused segregation of elements at the grain boundary cauing IGC attack, while the ratio of Cu and Zn is importnat in determining the susceptiblity due to the difference in the electrochemical potential. Grain boundary misorientation angle showed considerable influence on grain boundary chemistry (presence of Cu, Zn or related precipitation, and precipitate free zone) and infuenced intergranular corrosion. High angle and CSL grain boundaries are highly susceptible to IGC for immersion time around 24h or less. However, increasing the immersion time to 72 h showed that all types of grain boundaries were subjected to severe intergranular corrosion. Moreover, low angle grain boundaries were subjected to a certain degree of ICG even for immersion time 24h.