The government says that the changes in defence policy are vital to meet new military challenges such as those posed from a rising China.
But China's defence ministry said on Saturday they "run counter to the trend of the times that upholds peace, development and co-operation", the Xinhua news agency reports.
"The move has breached the restrictions of Japan's pacifist constitution," the ministry added.
Many Japanese who opposed the bills - which prompted large public protests - were also attached to the pacifist provisions in the constitution that banned fighting overseas.