In the past decade, there appeared many exact results in supersymmetric gauge theories thanks to localization method. These exact results are useful to study properties of perturbative series in quantum field theory (QFT) especially in the following two sense. First we can systematically analyze perturbative series around (non-)trivial saddle points in QFT. Second when we manage to obtain resummation of perturbative series without ambiguities in someway (e.g. Borel resummation and resurgence), one can explicitly see how the resummation is related to the exact result including non-perturbative corrections. In my talk I will demonstrate this in 3d N=2, 4d N=2 and 5d N=1 supersymmetric gauge theories on sphere. I will first discuss that we can show Borel summability of perturbative series by Yang-Mills coupling along real positive axis in 4d N=2 and 5d N=1 supersymmetric gauge theories with Lagrangians for various observables. It turns out that exact results in these theories can be obtained by summing over the Borel resummations with every instanton number. I will also discuss perturbative series in general 3d N=2 supersymmetric Chern-Simons matter theory, which is given by a power series expansion of inverse Chern-Simons levels. For this case we can prove that the perturbative series are always Borel summable along imaginary axis while it is not Borel summable along real positive axis often. It turns out that the Borel resummations along this direction are the same as exact results. I will also give physical interpretations of infinite singularities in Borel plane for this class of theories. [PRL116,no.21,211601(2016), PRD94, no.2, 025039 (2016) and upcoming paper(s)]