The collision of SL9 with Jupiter caused many new molecular species to be deposited in the Jovian stratosphere. We use a photochemical model to follow the evolution of the impact-derived species. Our results regarding the nitrogen and oxygen compounds are presented here. NH3 photolysis initiates the nitrogen photochemistry. Much of the nitrogen ends up in N2, nitrogen-sulfur compounds, and HCN, but NH3 and nitriles such as C2H3CN may also exist in observable quantities a year or so after the impacts. Oxygen species survive for a long time in the Jovian stratosphere. The only major oxygen-containing compounds that exhibit dramatic changes in the lower stratosphere in the first year following the impacts are SO, SO2, and OCS-H2O, CO2, and CO are comparatively stable. We discuss the important photochemical processes operating on the nitrogen and oxygen species in the Jovian stratosphere, make predictions concerning the temporal variation of the major species, and identify molecules that might act as good tracers for atmospheric dynamics. ¿ American Geophysical Union 1995