Abstract: In this paper, the programming language ConC++ is introduced, which is extended from C++ to support multithread and concurrent programming using concurrent classes and protected classes. A concurrent class has an active function, which executes immediately when an object is instantiated. A protected class encapsulates a group of data and operations on them. It is used to implement synchronization and mutual exclusion between objects of concurrent classes, with the centralized object concurrency control. The approach achieves object autonomy, decreases context switches and deadlocks and increases program performance.