The conceptually oriented design knowledge acquisition system described in this paper is a very general knowledge acquisition environment which understands basic logic and language. The system contains ideas from artificial intellegence (ai), object-oriented programming (oop) and logic programming (Ip). Knowledge is organized into small unit termed conceptual Descriptors (cds) in the system which are analogous to frames in ai or objects in oop. Cds are defined by a number of properties such as attributes, logic constraints and functional equations,and arranged in inheritance hierarchies.There are some semntic subsystems such as afirst order logic subsystem and simple natural language subsystem which are used to perform various types of semantic checks and debug logically redundancy,contradication and non-consistence about knowledge.The system is intended to assist in the process of developing descriptions,definitions,or specifications of system under design,or ti describe existing system for documentation or teaching purposes.Typical applications would include most kinds of expert system and software system.