Chemical glue is often used to encapsulate fiber-optic F-P interterometnc sensor to fixup the F-P cavity, Which is easy to come unglued as aging. A new encapsulation method to melt fiber and quartz glass tube by high-frequency CO2 laser is put forward. The experimental results show that the average cost of power can be as low as 0.1 dB if the proper power of laser pulse is chosen,which can satisfy the demand of encapsulation,and thus the method has applicable value.