Xue, who won gold in partnership with Zhang Xi in Fuzhou last year, and Xia first beat Varapatsorn Radarong and Tanarattha Udomchavee from Thailand in the second round of the single elimination phase 2-0 (21-17, 21-16) in the morning.
They then faced Lima and Talita, nailing a straight-set victory in just 38 minutes to send hundreds of raucous home crowd on fire.
"The Brazilian pair seemed a little bit impatient after the start, while in the second set the crowds chanted cheers for me and Xinyi, they might be affected by that," said Xue, who is a Fuzhou native.
Lima blamed their defeat on unforced mistakes.
"At the moment, I'm feeling sad, because we lost the game," Lima said afterwards. "In the first set we had some faults. In the second set my team were well insideout and serve. But finally we lost. Congratulations to the Chinese team."
Xue and Xia will next meet three-time Olympic champion Kerri Walsh and April Ross in the semifinal on Sunday. The experience American pair booked their place in the final four after beating Wang Fan and Yue Yuan, also from China, 2-0 (21-17, 21-18).
The other semifinal will be an all-Brazilian affair, featuring Juliana Felisberta Da Silva/Maria Antonelli and Maria Clara Salgado Rufino/Carolina Solberg Salgado.
In the morning Juliana and Antonelli defeated Tanja Goricanec and Tanja Huberli of Switzerland 2-0 (21-16 24-22), before they beat Marta Menegatti and Viktoria Orsi Toth from Italy 2-0 (21-18, 21-15) to reach the semis.
Maria Clara and Carolina had to fight hard all day, playing three sets in the second round of knock-out phase and in the quarters.
Fuzhou, capital of the Fujian province lies on the southeast coast of Chinese mainland and hosts the Open event for the second straight year.
In addition to the Fuzhou Open, two other stops are scheduled in China in 2014 on the FIVB international schedule: the FIVB Shanghai Grand Slam (April 29 to May 4) and the FIVB Xiamen Open (October 7 to 12). All three are double-gender events.
photos Janos Schmidt