Previous studies have investigated influencing factors of early discontinuation of breastfeeding, but few studies have developed an easy-to-use tool to identify risk of breastfeeding cessation at 6 months after birth. This research team aimed to develop and validate an exclusive breastfeeding duration risk nomogram in Chinese mothers. A longitudinal cohort survey was conducted. Data were collected from 394 postpartum women in three hospitals in Hubei Province, China from December 2017 to December 2018. The LASSO regression model was used to screen for optimized factors in an exclusive breastfeeding duration model. Multivariable logistic regression was applied to construct a prediction model. Discrimination and calibration were assessed using a C-index and calibration curve, and internal validity was established using bootstrapping validation. Factors integrated in the prediction risk nomogram were monthly household income (odds ratio [OR] = 1.31, 95% confidence interval [CI]: [0.95, 1.80]), experiences of breastfeeding (OR = 1.23, 95% CI: [0.92, 1.63]), attitude (OR = 1.72, 95% CI: [0.94, 3.16]), self-efficacy (OR = 2.45, 95% CI: [1.40, 4.29]), perceived insufficient milk supply (OR = 0.12, 95% CI: [0.06, 0.25]) and postpartum depression (OR = 0.06, 95% CI: [0.02, 0.17]). The model displayed good discrimination with a C-index of 0.87 (95% CI: [0.84, 0.91]) and good calibration. The C-index interval validation was confirmed to be 0.86. This study resulted in the development of a novel nomogram with good accuracy to aid healthcare professionals in assessing the probability of a mother discontinuing exclusive breastfeeding at the breast before 6 months.