Precision medicine uses data of a person’s genomic profile, proteins, environment and lifestyle to prevent to diagnose and to treat the disease. Traditional pathology heavily depends on the tumour typing, differentiation and grading. In contrast, the precision medicine emphasizes on unique molecular and phenotypic characteristics of individual patients. Computational Cytology (pathology) with the help of artificial intelligence (AI) plays a pivotal role in the interpretation of clinical, whole slide imaging (WSI) of histopathology and cytology, biomarkers along with molecular data. The key components of precision medicine include genomic profiling, big data and bioinformatics, electronic health records, biomarkers, and preventive and public health data. AI can play an important role in precision medicine by cancer screening, cancer diagnosis, molecular data analysis, treatment planning and predicting prognosis. This chapter discusses the role of Computational Cytology and AI in personalized medicine.