Provincial Deputy Chairman Nguyen Cong Truong said there were over 1,000 containers waiting to enter China via Tan Thanh Border Gate as of Wednesday.
The proposed suspension would last 15 days starting Thursday, as it could take 20 to ease congestion.
China imposed more stringent import measures earlier this month to prevent entry and further spread of the novel coronavirus.
It only allows trade via five border gates in Lang Son, compared to 12 before, each operating for only five hours a day, compared to the usual 9-10 hours.
The number of containers, mostly carrying fruit, have dropped from 1,200 in March to 300 last week, then to 50.
China has rejected a Lang Son proposal to open its border gates for the same duration as before.
The Ministry of Agriculture and Rural Development had earlier advised traders to stop sending goods to China via border gates to avoid a pileup.
First quarter fruit exports to China, the largest buyer of Vietnamese agriculture produce, fell 29.4 percent year-on-year to $300 million as the Covid-19 pandemic halted normal trade, according to the Ministry of Agriculture and Rural Development.