  It has been proposed that magnetic activity could be enhanced due to
interactions between close-in massive planets and their host stars. In this
article, I present a brief overview of the connection between stellar magnetic
activity and exoplanets. Stellar activity can be probed in chromospheric lines,
coronal emission, surface spot coverage, etc. Since these are manifestations of
stellar magnetism, these measurements are often used as proxies for the
magnetic field of stars. Here, instead of focusing on the magnetic proxies, I
overview some recent results of magnetic field measurements using
spectropolarimetric observations. Firstly, I discuss the general trends found
between large-scale magnetism, stellar rotation, and coronal emission and show
that magnetism seems to be correlated to the internal structure of the star.
Secondly, I overview some works that show evidence that exoplanets could (or
not) act as to enhance the activity of their host stars.
