This study aims to determine the business processes of construction companies and analyze their accounting system requirements. This research uses a descriptive qualitative approach. It was conducted on 2 MSMEs in construction services (namely SUJM and SA) in North Sulawesi with business scales of K and M. To collect data, researchers used in-depth interview techniques. Intensive interviews were conducted with 4 informants such as the owners and the project manager from SUJM and SA companies to explore their perspectives on the overview of the entity, business activities, and business transactions. Data collection is also done through literature studies about accounting systems, internal control, and systems analysis. After collecting and reducing the data, we present the data focused on the construction company's business flow and the accounting system's needs. The researcher conducted a system requirements analysis with the stages of preliminary analysis, preparation of proposals for the implementation of system analysis, implementation of system analysis, and preparation of reports on the results of system analysis. From the results of the analysis, the researcher concludes an accounting system is needed by construction companies. The results show that the construction business process consists of project information, prequalification, tender, contract, execution, and product submission. Based on business processes and system analysis, the accounting system in construction companies includes the main accounting system, namely the reporting system, and the supporting accounting system, namely the cash receipts and disbursements system. The existence of the accounting system will assist the company in coordinating and monitoring its operational activities and make it easier for companies to prepare financial reports and tax reporting. This research has a practical contribution to construction companies in developing countries in building their accounting systems.