Abstract: As urban parks become more open and increasingly associated with the urban space, how to build a secure environment for parks has become a hot topic in academia. To study the security of urban parks, we cited the South Lake Park of Tangshan City as an example. On the basis of field investigations and references to related theoretical researches, we established a security evaluation system for the urban park space based on the six elements of CPTED. By collecting data with questionnaires, we applied the fuzzy comprehensive evaluation method to get the tourist satisfaction with the South Lake Park. The result shows that from high to low, the satisfaction values to the security are image and maintenance, territoriality, surveillance, access control, activity support and target enhancement. According to researches on 23 index factors of the five indicators, six optimization strategies including optimizing the layout and design, strengthening the deterrence, maintaining a good environmental image and enriching the activities of the park space are proposed. These optimization strategies will provide references for related planning and environmental designs of the South Lake Park.