Blockchain-based decentralized applications have been providing robust, reliable, and durable services in multiple fields, such as encrypted digital currency, cloud storage, and Internet of Things. However, the throughput capacity of blockchain can no longer meet the increasing performance requirements of decentralized applications. Sharding is the current mainstream performance optimization technology for blockchain. Nevertheless, the existing blockchain sharding approaches, mainly focusing on transactions among users, are not always applicable to decentralized applications dominated by the transactions of smart-contract invocation. To solve the above problem, this study designs and implements the consortium blockchain system BETASCO based on smart contract-oriented sharding. BETASCO provides a shard that serves as an independent execution environment for each smart contract, routes transactions to the shards holding the target smart contracts by a contract location service based on the distributed hash table (DHT), and supports communication and collaboration needs across smart contracts by availing the asynchronous invocation mechanism among smart contracts. By virtualizing the nodes, BETASCO allows each node to join multiple shards to support parallel executions of multiple smart contracts on the same set of nodes. The results of experiments show that the overall throughput capacity of BETASCO linearly increases as the number of smart contracts grows, and the throughput capacity for the execution of a single smart contract is comparable to that of HyperLedger Fabric.