Abstract The iron gall inks were one of the writing materials mostly applied in historical documents of the western civilization. Due to the ink corrosive character, the documents are faced with a danger of being seriously, and in some cases also irreversibly changed. The elemental composition of the inks is an important information for taking the adequate conservation action [Project InkCor, http://www.infosrvr.nuk.uni-lj.si/jana/Inkcor/index.htm , and references within]. Here, the in-air PIXE analysis offers an indispensable tool due to its sensitivity and almost non-destructive character. An experimental approach developed for precise and automatic analysis of documents at Jožef Stefan Institute Tandetron accelerator is presented. The selected documents were mounted, one at the time, on the positioning board and the chosen ink spots on the sample were irradiated by 1.7 MeV protons. The data acquisition on the selected ink spots is done automatically throughout the measuring pattern determined prior to the measurement. The chemical elements identified in the documents ranged from Si to Pb, and between them the significant iron gall ink components like Fe, S, K, Cu, Zn, Co, Mn, Ni were deduced with precision of ±10%. The measurements were done non-destructively and no visible damage was observed on the irradiated documents.