While pregnancy smoking stigma is widely acknowledged, no psychometrically sound tool to measure it exists. This study was designed to build the Pregnant Smoker Stigma Scale -Public Stigma (P3S-PS) for assessing the stigma of pregnancy smoking in the general French population. A total of 342 adults were recruited online to take the P3S-PS and some items (condemnation / rejection, and support for punitive actions) from other scales.Exploratory factor analysis was performed. Measurement invariance was tested according to gender and smoking status. Temporal reliability was checked after two weeks (n=72). The P3S-PS has 26 items and four dimensions: "derogatory cognitions," "negative emotions and behaviors," "personal distress," and "information provision." All dimensions were correlated (r=.36 to .75) and have good internal consistency (α.>.70), temporal reliability (ICC>.75), and measurement invariance. Validity is exhibited through the P3S-PS's association with condemnation and rejection (r=.32 to .53), support for punitive actions (r=.35 to .65), and presence of pregnant smokers in the close circle (r= -.23 to -.40). The P3S-PS is a promising tool that exhibits good psychometric qualities. This scale will be useful to trigger research regarding the stigma of smoking while pregnant.