Federated learning (FL) is a newly emerging distributed learning paradigm that allows numerous participating clients to train machine learning models collaboratively, each with its data distribution and without sharing their data. One fundamental bottleneck in FL is the heavy communication overheads of high-dimensional models between the distributed clients and the central server. Previous works often condense models into compact formats by gradient compression or distillation to overcome communication limitations. In contrast, we propose FedCliP in this work, the first communication efficient FL training framework from a macro perspective, which can position valid clients participating in FL quickly and constantly prune redundant clients. Specifically, We first calculate the reliability score based on the training loss and model divergence as an indicator to measure the client pruning. We propose a valid client determination approximation framework based on the reliability score with Gaussian Scale Mixture (GSM) modeling for federated participating clients pruning. Besides, we develop a communication efficient client pruning training method in the FL scenario. Experimental results on MNIST dataset show that FedCliP has up to 10%~70% communication costs for converged models at only a 0.2% loss in accuracy.