Investigation on up-con version of 10.6m radiation in proustite is reported. Under phase-matched conditions and pumped with a free-running pulsed ruby laser (λp= 0.6943μm) (W=0.2kW/cm2) the maximum power conversion efficiency is 1.6×10-5.The optimum phase-matching angle is 2630 10 and the curves η(Q) and η(W) were measured. The results are discussed.