The diagenesis of sediments is profoundly impacted by porosity and permeability since these parameters control the flow of fluids through rocks that build up mineral authigenesis, cementation, and dissolution. Porosity in rock is available in sedimentary rock, particularly in sandstone in Cipacar formation located in Banjarsari, Lebak, Banten. This research aims to examine sandstone characteristics, porosity value, diagenesis process, and implication between porosity and diagenesis. The data of this study were obtained from surface outcrops and petrographic analysis. Results of this research show that sandstones in Cipacar formation have porosity values between 8-14 % and have undergone diagenesis processes such as compaction, cementation, and dissolution which are classified in the mesogenesis regime. © 2021 Journal of Physics: Conference Series.