  We explore the electromagnetic fields around a quasi-Kerr compact object
assuming it is immersed in an external asymptotically uniform magnetic field.
Using the Wald method, components of the electromagnetic field in orthonormal
basis have been obtained. We explore the charged particle motion around
deformed Kerr compact objects in the presence of external asymptotically
uniform magnetic fields. Using the Hamilton-Jacobi equation, we obtain the
effective potential expression for the charged particle surrounding a
quasi-Kerr compact object immersed in an external magnetic field. It is also
derived the dependence of innermost stable circular orbits (ISCOs) from the
magnetic and deformation parameters for charged particles motion around a
rotating quasi-Kerr compact object. Comparison with ISCO radius measurements
has provided the constraint to the deformation parameter as $\epsilon \gtrsim
-0.012$. The center of mass (CM) energy of the colliding particles in several
physically interesting cases has been studied.
