The present study was made to determine the binding patterns of several lectins to the surface coat (SC) proteins of various isolates and developmental stages of the pine wood nematode (PWN), Bursaphelenchus xylophilus. Also, the detailed characteristics of the SC proteins were profiled by using molecular techniques. The lectin-binding study demonstrated the stage-specific characters of SC in binding to the lectin, wheat germ agglutinin (WGA). WGA binding was observed only to the outer surfaces of third-stage propagative juveniles and to the egg shells, and this occurred more frequently in virulent than in avirulent PWN isolates. A greater variety of lectins bound to eggs than to any other life stage. For characterisation, the SC proteins extracted were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and analysed by lectin blotting. The results showed that the carbohydrate and protein patterns of the SC of the PWN changed during nematode development.