This dataset accompanies the manuscript entitled "Microenvironmental Confinement Drives Density-Dependent Neuron-Like Cell Proliferation and Contact-Dependent Neurite Outgrowth," and contains microscopy images (.tiff) and associated raw tracing data (.csv, *.swc, .traces) collected using Fiji's Simple Neurite Tracer plugin. Data was generated from PC12 cells cultured within 3D-printed confinement structures, acquired using an Olympus IX-81 inverted microscope. Python scripts (.py) are provided to replicate analyses such as data filtering, statistical testing, and figure generation described in the manuscript. The dataset is structured by experiment IDs and days in vitro (DIV), facilitating detailed examination of neuron-like cell proliferation and neurite growth patterns under varied confinement conditions.