This study aimed to evaluate the effect of glide‐path preparation and coronal pre‐flaring on torque generation of rotary nickel–titanium files. Sixty mesiobuccal root canals of 3D printed resin teeth (Dentalike) were randomly divided into 4 groups (n = 15) according to the preparation method; Group 1: OneCurve only; Group 2: OneG and OneCurve; Group 3: OneFlare and OneCurve; Group 4: OneFlare, OneG, and OneCurve. During the final canal preparation procedure, the torque generated was recorded. The sum of generated torque and maximum torque were calculated. Statistical analysis was performed with one‐way ANOVA and Duncan's post hoc comparison. The summed torque was reduced by glide‐path preparation and coronal pre‐flaring (P 0.05). It will be advantageous to create a glide‐path with coronal pre‐flaring to reduce the stress and reactive forces to the NiTi file and root dentin.