Silver nanoparticles (AgNPs) from marine invertebrates, particularly sea cucumbers, are relatively few or even lacking. This study aimed to determine the potential of the body wall of Bohadschia marmorata as reducing agent to synthesize silver nanoparticles and characterize the generated AgNPs using a direct and environment-friendly procedure. Although limited, the generated AgNPs were confirmed with an absorbance peak of 416 nm, indicative of surface plasmon resonance, with strong signals of elemental silver acquired by EDS at 3 keV. The potential functional groups responsible for the reduction of silver ions and capping of the nanoparticles include O–H (alcohol and carboxylic acids), C–C (alkene), N–H, and C–N (amine) groups detected by FT-IR. Scanning electron microscopy showed a nearly spherical morphology with an approximate size of 288 nm which tends to polydisperse and aggregate. Thus, this study showed that the sea cucumber body wall can be used in the biosynthesis of AgNPs. However, refinement of the procedures and operational parameters used is needed to produce more and better-quality nanoparticles.