Sharks occupy the top trophic level in the marine community and play an important role in maintaining ecosystem stability and diversity. The stock status of shark species is often difficult to assess by formal stock assessment methods due to limited fishery data. Blue shark () is the most widely distributed pelagic shark species in tropical and temperate oceanic waters. This species is often caught as bycatch in oceanic longline fisheries that target billfishes and tunas, and also in the artisanal longline fisheries that operate in coastal areas such as Chile. Because of its slow growth and late maturity, the blue shark is defined as "Near Threatened" globally in the IUCN species list. Determining the stock status of Indian Ocean blue shark using a data-poor approach has been assigned as a high research priority by the Indian Ocean Tuna Commission. In this study, we assessed the Indian Ocean blue shark stock status using the depletion-corrected average catch (DCAC) approach and Monte Carlo simulation. DCAC is a data-poor approach that only needs basic biological information (natural mortality, was estimated by the Hoeing method, resulting in a mean of 0.05. In addition to the annual catch data, the application of DCAC also needs the means and standard errors of the following parameters:depletion of the biomass (. First, we estimated the sustainable yield () of blue shark using abundance indices (standardized catch per unit effort[CPUE] time series) derived from different longline fleets (i.e., Spain, Portugal, Japan, and Taiwan, China). Second, we evaluated the sensitivity of DCAC by considering multiple combinations of different levels of , CPUE indices, and lengths of time series of data. Lastly, we summarized the estimated values and compared our estimates with the results from other assessment approaches for this species. The results showed that when F_MSY/M when was close to zero or negative. The results were sensitive to the CPUE index. The estimated was reliable and close to the maximum sustainable yield (estimated from other assessment models) when the Japanese longline CPUE index (1998-2014 or 2001-2014) was used. The current (2014) annual catch of blue shark might be at or just above the estimated maximum sustainable yield, although the estimate is subject to uncertainties. This study suggests that DCAC is suitable for estimating the of Indian Ocean blue shark using catch data and CPUE indices as the main sources. This study also provides guidelines for the application of data-poor approaches in domestic fisheries of China.