Assessing the extent of biological resources damage resulting from oil spill could help the government meet the necessary requirements to develop policies on marine biological damage compensation and biological restoration. There have been a lot of researches conducted to assess the damage resulting from oil spill by using revealed and expressed preference techniques. Those researches provided some approaches to quantify the biological damage, and some useful management suggestions for government as well. However, the techniques used for assessing the damage remain controversial because some techniques tend to overstate actual losses and some computer programs cannot reflect reality accurately. Resource Equivalency Analysis (REA) is a tool for assessing biological resource damage which has been used in United States and other countries to identify restoration project for biological resource injured by oil spill and other anthropogenic actions. Termed "resource-resource", REA seeks to determine the amount of restoration needed to compensate the biological resource losses. Penglai 19-3 oil field, located in Bohai Bay, attracted much attention due to the accident of oil spill in June, 2011. Data from the investigation report revealed by State Oceanic Administration showed that the accident caused a lot of damage. The damage extents of benthos and non-Benthos are 30% and 71.4%, and the damaged areas are 1600 km²and 6400 km², respectively. This paper assumes the marine ecological reserve as the restoration project, which could be built by releasing fish fry, building artificial fish reef, making sea grass bed and so on. The scale of the marine ecological reserve should be 1059km² to achieve the initial level. REA is based on the provision that restoration services are equivalent to the level of marine biological resource damage, and this method requires discounting the future cost and benefit. Parameter sensitivities are analyzed and it turns out that some parameters of restoration could affect the result significantly: the maximum annual output of biological resource, starting time of restoration project and the service period. The increased of the maximum annual output could lead to a reduction of the scale of marine ecological reserve. It could also lead to a reduction if we build the restoration project soon and lengthen the service period, so the restoration project is indeed needed to be built up and come into play as soon as possible. This paper concludes that REA offers an alternative to traditional analysis to assess the biological damage. What's more, the results could be used as a reference for government to conduct biological damage assessment and restoration. Applying the REA method in assessing the biological resource damage is only in the beginning stages, and the theoretical discussion have not yet commenced. However, it provides a prospect for the continuation of in-depth empirical research into the future.