Mr. Shahjahan qualified as a Chartered Accountant (CA) in 2019 and became a member of the Institute of Chartered Accountants of Bangladesh (ICAB). He possesses expertise in Audit & Assurance, Business & Finance Management, Taxation & VAT services, and handling special assignments. Mr. Md. Shahjahan is actively involved in auditing the accounts of various entities, including Banks, Multinational Corporations (MNCs), Public Limited Companies (PLCs), Ready-Made Garment (RMG) Industries, Non-Governmental Organizations (NGOs), Gas Transmission & Distribution companies, Exploration & Drilling companies, and Tea Industries, among others.

His professional experience extends to roles such as Chief Financial Officer and General Manager of Finance & Accounts in diverse organizations, including Fu-Wang Groups, Nahar Agro Group, Kazi Firm Group, Elephant Brand Cement, Sena LPG, Sena Edible Oil, OMC Group, United Commercial Bank Limited, Myone Electronics Ltd, and ASA International.