This study presents the characterization of parenchyma and vascular bundle of oil palm (Elaeis guineensis Jacq.) trunks harvested in Ladang Pelam, Kedah, Malaysia. Samples cut from outer, middle, and inner parts of the trunks were stored in a room at a temperature of 29°C for 0, 45, and 60 days prior to any tests. Parenchyma cells and vascular bundles from each sample were manually separated for microscopic analysis. Both light microscopy and scanning electron microscopy were employed to determine cell type, their distribution, and modification as a function of storage time. Based on the results of this work, the outer parts of the trunks had a larger amount of vascular bundles than the inner and middle parts. Moisture content of the samples from the inner part of the trunks was significantly higher than other parts. It appeared that the amount of parenchyma cells was decreased while the vascular bundle was increased in all three parts of the trunks with increased storage time.