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In the present paper, we study numerically the equatorial lensing andquasiequatorial lensing by Kerr black hole pierced by a cosmic string in thestrong deflection limit. We calculate the strong deflection limit coefficientsand the deflection angle, which are found to depend closely on the cosmicstring parameter $\beta$ and dimensionless spin $a_{*}$. The magnification andpositions of relativistic images are also computed in the strong deflectionlimit and a two-dimensional lens equation is derived. The most important andoutstanding effect is that the caustics drift away from the optical axis andshift in the clockwise direction with respect to the Kerr black hole. For fixed$a_{*}$ of the black hole, the caustics drift farther away from the opticalaxis for a large value of $\beta$. And for fixed $\beta$, they drift fartherfor high $a_{*}$. We also obtain the intersections of the critical curves withthe equatorial plane, which decrease with $a_{*}$ and $\beta$. In particular,we obtain a quantity $\bar{\mu}_{k+1}/\bar{\mu}_{k}$, which is independent ofthe black hole spin and mass. Thus, through measuring it, one is allowed todetermine the value of $\beta$ from astronomical observations.

Equatorial and quasi-equatorial gravitational lensing by Kerr black hole pierced by a cosmic string