Determining planktonic larval species composition and abundance data can serve to elucidate local patterns of distribution, determine an area's importance as a nursery ground, and help clarify broad-scale trends of adult distribution and spawning ranges. Although the Saco River and estuary is the fourth largest waterway system in Maine, this ecosystem has remained relatively unstudied over the last thirty years, and research describing the temporal ichthyoplankton composition and distribution is virtually absent. The present study examined the structure of the ichthyoplankton community and determined the temporal and spatial variation in species diversity and abundance within the Saco Bay estuary system. Weekly sampling trips during the months of June, July, and August in 2007 revealed ten species of ichthyoplankton present in the study area. Ulvaria subbifurcata (Radiated Shanny) and Tautogolabrus adsperus (Cunner) dominated the abundance data followed by Hippoglossoides platessoides (American Plaice) and Myoxocephalus octodecimspinosus (Longhorn Sculpin).