Objectives: High plasma creatine kinase (CK) activity is associated with hypertension in the general and pregnant population. We hypothesize that women with a history of early-onset preeclampsia are prone to hypertension due to a high CK activity level. Study design: Nine to 16 years after pregnancy, serum CK activity and blood pressure were measured in 117 women with a history of early-onset preeclampsia and 50 women with a history of an uncomplicated pregnancy. Main outcome measures: CK activity levels of the two groups were compared using the Mann-Whitney U test. The association between CK activity and blood pressure was evaluated by means of multivariable regression analysis. Results: There was no significant difference in median (interquartile range) CK activity between women with a history of early-onset preeclampsia and an uncomplicated pregnancy (59.00 [47.00–85.00] vs. 58.00 [46.50–75.25], respectively, p = 0.774). The association between CK and systolic blood pressure was significant in women with a pregnancy history of early-onset preeclampsia (regression coefficient [95% confidence interval]: 0.123 mmHg [0.020–0.226], p = 0.019), and a trend was found for diastolic blood pressure (p = 0.069). CK and blood pressure were not significantly associated in women with a history of an uncomplicated pregnancy. Conclusions: Median CK did not significantly differ between the two groups. Serum CK activity was significantly associated with systolic blood pressure in women with a history of early-onset preeclampsia. These data suggest that CK is not a predominant factor in the increased risk of hypertension in women with a history of early-onset preeclampsia.