Objective To explore the difference of T wave amplitude in different sex and the incidence of low T wave in normal people. Methods A total of 575 subjects（270 males and 305 females

aged 20～87 years） were enrolled in the study

and divided into ten groups according to gender and age. The 12 lead synchronous ECG was recorded in all subjects. The T wave amplitude of each lead was measured and the incidence of low T wave in different lead combinations was counted. Results T-wave amplitude in leads Ⅱ

Ⅲ

aVF

V

1

～V

6

was higher in males than in females（p

<

0.01）

and that in leads AVR was higher in males than in females（p

<

0.05）; In subgroup

T-wave amplitude was the most significant difference between men and women aged 20～49

mainly in leads Ⅱ

Ⅲ

aVF

V

1

～V

6

（p

<

0.01）; Over 50 years old

T-wave amplitude difference between men and women diminished

The differences leadsgradually weakened and disappeared in leads Ⅱ

Ⅲ

aVF

V

1

and V

4

～V

6

; The T-wave amplitude of lead V5 decreased with age in men（p

<

0.05） and the T-wave amplitude of lead Ⅱ decreased but had no significant difference（p>0.05）; The T-wave amplitude of lead Ⅱ and V5 increased but had no significant difference with age in women（p>0.05）;The incidence of low T-wave was 21.43% in women and 5.56% in men（p

<

0.05）. Conclusions There are differences related to gender and age in T wave amplitude of normal people’s ECG. Meanwhile there are a high incidence of low T wave in Normal women’s ECG. So it is imperative to establish our own ECG diagnostic standard.