WASHINGTON—The flow of investment money between China and the U.S. continued to decline in the first half of 2019 as trade tensions took their toll, according to a new report.

The value of foreign direct investment and venture-capital deals between the two countries fell to $13 billion during the first six months of the year, a decline of 18% compared with the previous six-month period, according to data released Thursday. Investment is down 49% from the first half of 2018.

The $13 billion figure marks the lowest value since 2014, a sign of investor anxiety over stalled trade negotiations, tougher U.S. scrutiny of foreign deals and the Trump administration’s restrictions on telecom giant Huawei Technologies Co., the report says.

“Cross-border investments have become one of the first major casualties of U.S.-China tensions,” said Thilo Hanemann, one of the report’s authors and a partner with research firm Rhodium Group. “You can really see that in the numbers.”

Rhodium Group released the report with the National Committee on U.S.- China Relations, a nonprofit that promotes cooperation between the two countries.