The Smooth Hammerhead is caught globally as target and bycatch in coastal and pelagic commercial and small-scale longline, purse seine, and gillnet fisheries, and is often retained for the fins, and sometimes the meat. It has undergone steep historic declines in the Atlantic but the introduction of management measures may be allowing slow recovery, lesser declines in the South Pacific, and increases in the Indian Ocean. The weighted global population trends estimated a median reduction of 21.8–64.8%, with the highest probability of <20% and >80% reduction over three generation lengths (72.3 years). The Northwest Atlantic data that includes the period after management changes led to the lower estimated global reduction. However, there is uncertainty in some of the catch data, limited regional representation of some time-series, and intensive-fisheries in data-poor regions that are suspected to have driven declines, balanced with the relatively lower level of artisanal fisheries threat to this species compared to that of the Scalloped Hammerhead (S. lewini) and Great Hammerhead (S. mokarran), due to its generally more temperate distribution. Expert judgement elicitation thus inferred a global population reduction of 30–49% and the Smooth Hammerhead is therefore assessed as Globally Vulnerable A2bd. More robust species-specific data and monitoring of catches is required to improve certainty of catch estimates for a future assessment of this species.

In the Mediterranean Sea, a meta-analysis of time series of standardized indices of abundance showed that hammerhead sharks (mainly composed of the Smooth Hammerhead) have declined by >99% in abundance and biomass since the early 19th century. As the situation in the Mediterranean region has not changed in terms of fishing effort, the species is likely to still be threatened given this steep decline alongside possible local extinctions in various region of the basin. The Smooth Hammerhead is therefore assessed regionally as Critically Endangered under Criterion A2bd.