The United States, Canada, France and Japan are among a number of countries that now require travelers from China to show a negative Covid test before arrival, as the country faces a surge in cases.
"Some countries have taken entry restrictions targeting only Chinese travelers," foreign ministry spokesperson Mao Ning told a regular briefing.
"This lacks scientific basis and some practices are unacceptable," she added, warning China could "take countermeasures based on the principle of reciprocity."
China is seeing a steep rise in infections after years of harsh zero-Covid restrictions were abruptly loosened last month with little warning or preparation, and hospitals and crematoriums have been quickly overwhelmed.
In late December, Beijing said inbound travelers would no longer be required to quarantine, sending many Chinese people rushing to plan long-awaited trips abroad.
Countries have cited China's lack of transparency around infection data and the risk of new variants emerging as reasons to restrict travelers.
China recorded only 22 Covid deaths since December, after dramatically narrowing the criteria for classifying such deaths.