A system of first-order differential equations is expressed in the form of
first-order Lagrange equations. Based on the theory of symmetries and conse
rved quantities of first-order Lagrange systems, the perturbation to the sy
mmetries and adiabatic invariants of first-order Lagrange systems are discu
ssed. Firstly, the concept of higher-order adiabatic invariants of the firs
t-order Lagrange system is proposed. Then, conditions for the existence of
the exact and adiabatic invariants are proved, and their forms are given. F
inally, an example is presented to illustrate these results.