This research was conducted in March-May 2014 in mangrove study central marine station Riau University in Dumai. This study aims to determine the effect of spacing on potential seedling survival and growth of Rhizophora apiculata. The method used in this research was experimental methods. Spacing treatment tested in this study were: (1) Planting with a distance of 25 x 25 cm (2) Planting with a…