A small-signal single-pass power gain of 14.76 and double-pass power gain of 26.31 have been measured for a Ti:sapphire amplifier. The results correspond to thesmall-signial gain coefficient being 1.81 cm-1 and the gain cross section being 2.74×10-19 cm2. The small-siginal gains for different wavelengths have been obtained. Thesaturation fluence and optimum length of Ti:sapphire have been calculated.