  We revisit the shadows of rotating braneworld black holes in the
Randall-Sundrum type II model, by considering not only the metric in the near
region of the black hole but also the linearized metric in the far region where
the observer stays. Our study is significantly different from previous studies,
which relies only on the metric in the near region. From the study, we identify
a critical angle $\theta_c$ which decides the shadow curve is open or closed:
the shadow curve would be open if the observational angle
$\theta_c<\theta_o\le\pi/2$, and the curve becomes closed when
$0<\theta_o\le\theta_c$. We study how various parameters affect the shape of
the shadow curve. We furthermore apply our analysis to the data of M87* from
the Event Horizon Telescope and obtain a new constraint on the parameters of
the braneworld black holes.
