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In the collinear factorization of the form factor for the transition$\gamma^* \pi^0 \to \pi$ the hard part contains double log terms. These termswill spoil the perturbative expansion of the hard part. A simple exponentiationfor resummation leads to divergent results. We study the resummation of thesedouble log's. We make an analysis to show the origin of the double log's. Withthe understanding of the origin one can introduce soft factors and NonstandardLight-Cone Wave Functions(NLCWF) to derive a factorized form for the formfactor, where the hard part does not contain the double log's. There is aperturbative relation between NLCWF and the standard Light-Cone WaveFunction(LCWF). Beside the renormalization scale $\mu$ the introduced NLCWF'sand soft factors have extra scales to characterize the double log's. Using theevolutions of the extra scales and the relation we can do the resummation ofthe double log's perturbatively in sense that LCWF's are the onlynonpertubative objects in the resumed formula. Our results with some models ofLCWF show that there is a significant difference between numerical predictionswith or without the resummation.

Resummation of Large Logarithms in the Electromagnetic Form factor of pion