  For the first time, we use the Event Horizon Telescope (EHT) data to
constrain the parameters of braneworld black holes which constrain
$\epsilon=0.0285^{+0.0888+0.1456}_{-0.0895-0.1475}$ for the anisotropic black
hole and $q=-0.0305^{+0.1034+0.1953}_{-0.0895-0.1470}$ for the tidal
Reissner-Nordstr$\ddot{o}$m (RN) black hole. Based on the fitted data and
physical requirement, we calculate the photon deflection, the angular
separation and time delay between different relativistic images of the
anisotropic black hole and the tidal RN black hole in the ranges
$-0.1190<\epsilon<0$ and $-0.1775 <q<0$. And furthermore, we study the
quasinormal modes (QNMs) for the braneworld black holes. The results shed light
on existence of extra dimension.
