Abstract <p>This study was carried out in a 23-year plantation, divided into three slope (S) groups (S &lt; 15%, 15%&#xa0;≤ S &lt; 35%, and S ≥ 35%), sampled from southern Türkiye in Taurus cedar (<i>Cedrus libani</i> A. Rich.). Tree height and diameter at breast height were studied to examine effect of slope on the characteristics in the plantation established 2 × 2.5 m. Third slope (S ≥ 35%) showed the highest tree height (5.9 m) and diameter at breast height (8.8 cm) performances, while they were the lowest in first slope (S &lt; 15%) (5.1 m and 8.1 cm). There were significant (<i>p</i> &lt; 0.05) differences among slope groups for tree height opposite to diameter at breast height according to results of analysis of variance. Diameter at breast height had higher variation than tree height in all slope groups based on coefficient variation. Positive and significant (<i>p</i> &lt; 0.05) relations between tree height and diameter at breast height in all slope groups according to results of correlation analysis. Results of the study were discussed for afforestation and other forestry practices of the species.</p>