Introduction: A genotoxic effect of formaldehyde (FA), particularly micronucleus (MN) induction and chromosomal aberrations (CA) has been shown in several previous studies. Aim of work: The aim of the present study was (1): to assess formaldehyde air concentration in different areas of mortuary and museum of Anatomy& Embryology department of Zagazig Faculty of Medicine (2) to measure frequency of micronuclei and chromosomal aberrations in peripheral blood lymphocytes of the workers and staff members working in the Anatomy & Embryology department of Zagazig Faculty of Medicine as a measure of formaldehyde carcinogenicity. Materials and Methods: A comparative cross sectional study was carried out in Anatomy & Embryology departments of Zagazig Faculty of Medicine, where 42 subjects (occupationally exposed to formaldehyde vapors) were participated in the study and similar number of unexposed subjects was included for comparison. Exposure assessment was performed by environmental monitoring for formaldehyde concentration in the air within the mortuary and museum using a specific apparatus. Evaluation of genotoxic effects was performed by application of micronucleus test and searching for chromosomal aberrations (CA) in peripheral blood lymphocytes of the included subjects. Results: Time weighted average concentrations of FA (TWA8h)