Erasing grid-line is a key in the Chinese handwriting auto-identify system.After analyzing the advantages and disadvantages of the existed grid-line erasing algorithm we present a grid-line erasing algorithm based on the block adjacency graph(BAG) devised by Pavlidis and the stroke reconstruction algorithm in this paper.Firstly

the scanning graph for Chinese handwriting is changed into the BAG by use of the chain structure

and then the proper Connected Sub-graph according to the BAG is searched.These connected sub-graphs are the grid-lines that should be erased.Finally

the strokes

which left by erasing grid-line

are reconstructed.Because it is easy to get the BAG

searching and erasing grid-lines will be very fast.At the same time

our algorithm can reconstruct the strokes after erasing grid-line

and it not only avoids the disturbing information but also remains the useful characters of Chinese handwriting.Experimental results show our algorithm has strong ability in anti-disturbance and good effect in erasing grid-lines.