Large num ber o f species o f wood is being im ported from al) locations of the world and grown in variety o f environm ents, into Turkey; their strength properties are largely unknow n. Present paper contains inform ation on the equations for the tree species o f known origin and density to estim ate their strength properties necessary for the engineering applications. They w ere developed by linear, exponential, geom etric, and polynom ial regression analyses.