We report the colloidal synthesis of monodisperse nanocrystals (NCs) of InSb, which is an important member of III-V semiconductor family. Colloidal InSb NC quantum dots showed well-resolved excitonic transitions in the near-infrared spectral range, with the optical band gaps tunable from similar to 1.03 eV (1200 nm) to similar to 0.71 eV (1750 nm) corresponding to 3.3 and 6.5 nm LnSb NCs, respectively. We observed size-tunable band edge photoluminescence that could be significantly enhanced by growing InSb/CdSe or InSb/CdS core-shell nanostructures. Films of InSb NCs capped with S-2-ions showed ambipolar charge transport.