The objective of this study is to investigate the content of heavy metals in paddy soils base on geological evidence composed of cultivated and yield of 2011-2012 in-season rice data by Geographic Information Systems. A field survey was conducted to investigate the heavy metals contamination of paddy soils in selected areas in Suphanburi and Chiangrai provinces. The total concentration of As, Cd, Pb in paddy soil was measured. Paddy soils were slightly polluted with the content of As exceeding the standard value.