THIS PAPER AIMS TO INVESTIGATE THE EFFECT OF THE VARIABILITY IN THE MECHANICAL AND CROSS-SECTION PROPERTIES OF CHILEAN RADIATA PINE ON THE LATERAL BUCKLING STRENGTH OF SLENDER WOODEN BEAMS. THE STUDY IS CONDUCTED NUMERICALLY THROUGH FINITE ELEMENT MODELING AND USING LINEAR EIGENVALUE ANALYSIS. THE NUMERICAL MODEL IS VALIDATED USING EXPERIMENTAL RESULTS AVAILABLE IN THE LITERATURE. TWO APPROACHES ARE EMPLOYED IN THE ANALYSIS, FIRSTLY A DETERMINISTIC APPROACH USING DESIGN OF EXPERIMENTS (DOE) TECHNIQUES TO ESTABLISH THE RELEVANCE OF THE PARAMETERS, AND SECONDLY A STOCHASTIC ONE, THROUGH MONTE-CARLO SIMULATION TO INVESTIGATE THE IMPACT OF EACH PARAMETER ON THE LATERAL BUCKLING RESISTANCE. VARIOUS DISTRIBUTION FUNCTIONS ARE CONSIDERED TO INVESTIGATE THE EFFECT OF UNCERTAINTIES IN THE MATERIAL PARAMETERS AND THEIR IMPACT ON THE CRITICAL BUCKLING MOMENTS. MOREOVER, SOBOL INDICES INDICATED THAT FROM THE TOTAL VARIABILITY OF THE DISTRIBUTION OF THE CRITICAL MOMENT, AN AVERAGE OF 50% OF THE VARIABILITY IS ATTRIBUTED TO THE SHEAR MODULUS ?LR, 37% TO THE LONGITUDINAL ELASTIC MODULUS ??, AND A NEGLIGIBLE PERCENTAGE OF THE GRAIN ANGLE ?.