In string theory, it is well known that any hard scattering amplitude inevitably suffers exponential suppression. We demonstrate that, if the string scale is Mₛ < 2TeV, this intrinsically stringy behavior leads to a dramatic reduction in the QCD jet production rate with very high transverse momenta pₜ >~ 2 TeV at CERN LHC. This suppression is sufficient to be observed in the first year of low-luminosity running. Our prediction is based on the universal behavior of string theory, and therefore is qualitatively model independent. This signature is alternative and complementary to conventional ones such as Regge resonance (or string ball or black hole) production.