The invention discloses a method for forecasting the 
engineering service life of a 
glass fiber reinforced plastic sleeve, which comprises the following steps of: 1, analysis of the working conditions, i.e. analyzing the working conditions and determining the main strained condition and the hygrothermal aging condition of the 
glass fiber reinforced plastic sleeve; 2, determination of safety coefficients, i.e. measuring relative mechanical properties by utilizing a 
test sample, measuring the stress of the 
glass fiber reinforced plastic sleeve by the field test and further determining the working safety coefficients of the glass 
fiber reinforced plastic sleeve; 3, establishment of a short-period hygrothermal aging function, i.e. carrying out hygrothermal 
aging test on the 
test sample for 1,000 hours to establish the hygrothermal aging function; and 4, forecasting of the 
engineering service life, i.e. selecting the 
safety coefficient according to the minimum rule, carrying out integration on the 
safety coefficient and the hygrothermal aging function to establish a glass 
fiber reinforced plastic sleeve 
engineering service life 
estimation model, setting the residual safety coefficients as 2 and extrapolating to 100 thousand of hours according tot he 
estimation model. The method can be used for accurately forecasting the engineering service life of the glass 
fiber reinforced plastic sleeve. The method has the advantages of time saving, economy and simple method.