The toilet, in a busy park in Pudong New Area, will have 10 unisex stalls, plus some urinals and a stall for disabled people.
The opening on 19 November will coincide with World Toilet Day.
Unisex facilities will spare officials having to decide how to share out male and female stalls, say reports.
"It is an apparent problem that women have to wait in lines for toilets," Fu Liping, an official involved in the project, was quoted as saying, by the Xinhua news agency.
The stalls will be more spacious than regular ones. To guarantee safety and privacy, there will be attendants and higher partitions between stalls.
But there are no plans yet to build more unisex toilets, as authorities are unsure whether citizens will embrace the idea.
Their caution seem to be well-grounded, as people online have been less than enthusiastic about the unisex lavatory.
"I don't really support the idea. After all, men and female are different," said Weibo user Zhu Zhu Xia.
Another Weibo user said: "The problem will be solved if they build double female toilets."