A pulsed Ti:sapphire laser tuning by a dispersion-Brewster beam-expanding prism is investigated. The coversion efficiency can be improved ～8% by feedback of the pump laser. The established tunable Ti:sapphire laser features a high laser output energy of 23 mJ/pulse,a high laser conversion efficiecy of up to 19%,and a linewidth of less than 0.01 nm.