The study was conducted on 751 workers of Ha Long ship-building factory. To diagnose silica-dust lung disease by lung X-ray according to the ILO standards (2000). Study result shows that the rate of doubts and contract BBPSi was 5.8 percent. Of which 1.9 percent is certainly getting BBPSi diagnosis (type 1/0 p or higher) and 3.9 percent were suspected contract BBPSi (type 0/1 p). The Ship shell factory has the highest rate of suspicion and contract BBPSi (10.0 percent), followed by Clean and paint factory (3.4 percent). Occupations have high rate of suspected infection and contracting BBPSi is abrasive blasting, type rust, sand blasting, abrasive contact, welding, painting (5.2 percent and 2.8 percent) and processing of shell, ship shell assembly, vapor cutting, machinery cutting (1.9 percent and 0.4 percent). Worker group with working age or = 10 years with suspected infection rate and getting BBPSi (13.8 percent and 6.7 percent) is higher oompared with those 10 years (0.4 percent and 0.2 percent), the differences were statistically significance with p 0.001.