We report temperature dependent electron spin resonance (ESR) experiments of Gd 3ΓΎ in CeIn 3 and in its reference compound LaIn 3 taken in crushed single crystals. For LaIn 3 a single Dysonian Gd 3ΓΎ ESR line with a nearly temperature independent g$2:020Γ°5Γ is observed, and its linewidth follows a Korringalike behavior as a function of temperature. From the Korringa rate (DH=DT$16 Oe=K) and g-shift (Dg$0:027) we have extracted the exchange parameter between the Gd 3ΓΎ local moments and the conduction electrons (ce) in this compound. This exchange parameter J fs % 20 meV was found to be ce wave-vector independent. For CeIn 3 , the Gd 3ΓΎ ESR spectra were found to be weakly temperature dependent and present partly resolved Gd 3ΓΎ fine-structure. Interestingly, for CeIn 3 , the g-shift with respect to the g-value of Gd 3ΓΎ in insulators is negative, in contrast to the positive g-shift found for Gd 3ΓΎ in LaIn 3 . These results suggests different electronic structure at the Gd 3ΓΎ site in the Kondo antiferromagnet host CeIn 3 . Possibly, Kondo effect may cause a decrease of the s-like conduction electron density of states at the Gd 3ΓΎ site, giving arise to an exchange interaction only between the Gd 3ΓΎ local moment and the Ce 4f electrons.