It could be a big blow for Renault.
The French firm's popular Zoe electric car was hit with a zero-star safety rating on Wednesday (December 8).
It's the third best-selling EV in Europe, behind only models from Tesla and Volkswagen.
Among factors cited for the downgrade was a reduction in the quality of side airbags compared with earlier models of the car.
The lowly score won't stop Renault selling the Zoe, but the rating is closely watched by consumers in Europe and beyond.
Euro NCAP's secretary general said it all suggested safety was slipping down the priority list amid the transition to EVs.
In a statement Renault said the Zoe was safe and met all required standards.
Its budget brand Dacia was hit with a one-star score for its popular Spring EV on the same day.
Dacia said its value-oriented cars can't be fitted with advanced features that customers won't pay for.
Wednesday marked only the third time that Euro NCAP has awarded a zero-star rating.
The same day saw five-star scores for vehicles from BMW and Mercedes-Benz.
Analysts say Renault may now feel pressured to replace or upgrade the Zoe sooner than planned.