"How to be a good mother？" It has become a problem for more and more mothers. From the beginning of pregnancy, this topic has been put in front of all expectant mothers. Usually women will imitate their mothers, but sometimes the answers given by native families are not so satisfactory. More and more people realize the trauma in inter-generational transmission. Psychological studies mostly focus on the influence of "bad mother" on children. In clinic, it is not uncommon for people suffering from "mother's disease" because of the influence of "bad mother". In such an era of urgent need for positive energy, how to arouse the positive power of mothers becomes urgent and necessary.

On the basis of summarizing and analyzing the predecessors' research, this study adopts the methods of questionnaire, experiment and interview to explore the structure of character strength of mothers, and how to activate the character strength of mothers through structured group sand table, so as to become a better mother and improve parent-child relationship. On the basis of exploring the structure of mothers' character strength, the Mothers' Character Strength Scale was compiled as an evaluation tool. Specific research is as follows:

Study 1: The first study summarizes the characteristics and typical behaviors of good mothers in children's minds through theoretical discussion, open-ended questionnaire, text coding and statistics, and constructs the theoretical structure of character strength of mothers.

Study 2: Based on the theoretical structure of character strength of mothers, the Mother's Character Strength Scale was compiled as an evaluation tool. Exploratory factor analysis was used to get the structure of character strength of mothers, and confirmatory factor analysis was used to test the structure of character strength of mothers with Mplus software.

Study 3: The present situation of character strength of 1894 mothers in China was investigated by self-designed questionnaire "Mother's character strength Scale".

Study 4: The children from 51 families and their mothers were selected as subjects for experimental intervention, and structured group sand table was used as intervention means to stimulate the character strength of mothers and improve the quality of parent-child relationship.

The results are as follows:

The "Mother's Character Strength Scale" developed in this study has good reliability and validity, and can be used as a measurement tool of mother's character strength.
Mother's character strength model includes 10 first-order dimensions and 2 second-order dimensions; the second-order "caregiver" dimensions include family care, rigorous prudence, friendly help, due diligence, teamwork; the second-order "educator" dimensions include insight guidance, self-discipline, democratic respect, social wisdom, open and fair.
The "caregiver" dimension of mother’s character strength is better; the character strength of mothers from non-only-child families is worse; the character strength of highly educated mothers is better, especially the "educator" dimension; the character strength of mothers is better with the increase of age, and "51-60 years old" mothers were the best.
Structural sandplay in groups has a positive effect on the improvement of the character strength of mothers, especially in the five aspects of self-control and self-discipline, friendliness and help others, democratic respect, social wisdom and openness and fairness.
Structural sandplay in groups has a positive effect on improving the quality of parent-child relationship.

Key Words：Mother ; Character Strength ; Group Sandplay Therapy