This study examined the relationship between project life cycle management and business growth of small and medium enterprises in Port Harcourt, Nigeria. The study determined how project planning, project execution, and project monitoring influence SME growth outcomes. A descriptive survey research design was adopted, and data were collected using structured questionnaires administered to SME operators. Data obtained from respondents was analyzed using Pearson Product Moment Correlation with SPSS version 22. Results revealed significant positive relationships between project planning and business growth (r = 0.519), project execution and business growth (r = 0.559), and project monitoring and business growth (r = 0.566), indicating that effective management across project phases enhances SME performance. The findings demonstrate that structured planning improves resource allocation, disciplined execution enhances operational efficiency, and monitoring strengthens decision making and organizational control. The study concludes that project life cycle management represents a critical managerial capability that promotes sustainable business growth among SMEs. Based on the findings, the study recommends adoption of formal planning frameworks, improved execution coordination, continuous monitoring systems, managerial training in project management practices, and institutional support programs to enhance SME capacity. Implementing these measures will improve efficiency, competitiveness, and long-term sustainability of SMEs operating in dynamic business environments.