The effects of cold rolling and annealing process on the microstructure and thermal expansion properties of Ni36 Invar alloy were studied in this work. The results show that the coefficient of thermal expansion （ abbreviated as CTE） is greatly reduced by the cold rolling treatment with a depression rate of 30%-75%. The average CTE i.e.，

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and

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decrease first and then increase with the increasing reduction rate of cold rolling. At reduction rate of 60%，

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is the lowest i.e.， 1.43×10

-6

K

-1

， which is 49.8% lower than that of raw material.As the annealing temperature increases from 700 ℃ to 900 ℃， the

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gradually increases from 2.59×10

-6

K

-1

to 2.70×10

-6

K

-1

， and then decreases to 2.47×10

-6

K

-1

at 1 000 ℃. When annealed at 700 ℃ for different period， the CTE increases continuously with the increasing time， the

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increases from 2.46×10

-6

K

-1

at 0.5 h to 2.74×10

-6

K

-1

at 6 h. The variation of CTE with cold rolling and annealing process are deeply discussed and analyzed from the perspective of cold rolling texture， density of dislocation and vacancy， recovery and recrystallization of cold-rolled microstructure， and grain growth.