Polarization of the scattered Λ has been measured in the reaction Λ+p→Λ+p. A total of 90 000 elastic events was recorded. Polarization was observed which decreased in magnitude with increasing momentum. For 0.1<~|t|<~0.4 GeV2 the polarization is P=-0.21±0.07 for p=110 GeV/c and is +0.01±0.04 at p=320 GeV/c. Results for 860 Λ̄-p elastic scatterings are also presented.