Polylactic acid (PLA), a biodegradable polymer, is gaining attention as a sustain- able alternative to steel in civil engineering, yet its fracture behavior under complex loading remains underexplored. This study examines crack propagation in PLA sam- ples with dual keyhole notches under tensile loading, integrating experimental tests, finite element simulations, and machine learning predictions. Six PLA specimens (200×50×10 mm, crack length 10 mm, angles 60° and 70°, notch radii 0.5–2 mm) were tested experimentally, while 400 samples (angles 1°–80°, radii 0.5–4 mm) were simu- lated in ABAQUS. Artificial Neural Networks (ANN) and Long Short-Term Memory (LSTM) models, implemented in MATLAB, analyzed the results. Experimental peak stress reached 33.3 N/mm 2 (0.5 mm notch, 60°), while simulations predicted up to 65.225 N/mm 2 (0.5 mm, 1°). ANN with Bayesian Regularization outperformed other models, offering precise predictions of crack behavior. These findings provide a fracture criterion for PLA, advancing its potential in sustainable structural applications.