A new high-speed electron beam (EB) data conversion system has been developed for the variable-shaped beam EB reticle writing system EX-8. The target conversion rate from computer-aided design (CAD) data to EX-8 data is five reticles per hour for the class of 16-Mbit dynamic random access memory (DRAM) and beyond. To achieve this, both the hierarchical and parallel shape data operations and the parallel EB formatting have been adopted. Preprocesses for the hierarchical operations have been integrated, such as cell-overlap eliminations and the "doughnut process" which involves partially expanding shapes near cell boundaries. A 64-Mb DRAM design was successfully converted in the hierarchical method on an engineering workstation (EWS) with a single processor, and the number of processed shapes was reduced by four orders of magnitude and the average processing time was less than nine minutes. The processing time of the shape data operations for one layer of a 129 k gate array was reduced to 1/3 when four processes were performed in parallel on an EWS with four processors.