The value of bonds issued in China last month totaled 3.5 trillion yuan (about 508.8 billion U.S. dollars), down from 4.1 trillion yuan in June, official data showed.
Treasury bond issuance stood at 337.3 billion yuan, while local government bond issuance was 757 billion yuan, according to the People's Bank of China (PBOC).
Financial bonds issued last month were valued at 424.6 billion yuan, and corporate debenture issuance was 586.1 billion yuan.
By the end of July, total bonds outstanding reached 80.5 trillion yuan.
China has the world's third-largest bond market, which is growing rapidly and opening wider to overseas investors.
Last year, China issued bonds worth 40.8 trillion yuan, up 12.9 percent from the previous year, according to PBOC data.