We have performed magnetization, specific heat, and muon spin relaxation $(\ensuremath{\mu}\mathrm{SR})$ measurements on single crystals of the noncentrosymmetric superconductor ${\mathrm{Ir}}_{2}{\mathrm{Ga}}_{9}$. The isothermal magnetization measurements show that there is a crossover from type-I to type-II superconductivity with decreasing temperature. Potential multiband superconductivity of ${\mathrm{Ir}}_{2}{\mathrm{Ga}}_{9}$ is observed in the specific heat data. $\ensuremath{\mu}\mathrm{SR}$ measurement is performed to map the phase diagram of ${\mathrm{Ir}}_{2}{\mathrm{Ga}}_{9}$, and both type-I and type-II superconductivity characteristics are obtained. Most importantly, a more unique region with the coexistence of type-I and type-II $\ensuremath{\mu}\mathrm{SR}$ signals is observed. In addition, time reversal symmetry is found to be preserved in ${\mathrm{Ir}}_{2}{\mathrm{Ga}}_{9}$ by zero field $\ensuremath{\mu}\mathrm{SR}$ measurement.