Objective:To discuss the clinical efficacy and plausible mechanism of Tiao Yang Qu Xie(regulating Yang to eliminate pathogenic factors)needling method plus paroxetine in treating mild-to-moderate depression. Methods:Sixty-six patients with mild-to-moderate depression were divided into an observation group and a control group using the random number table method,each consisting of 33 cases.Another 25 healthy subjects were recruited as a healthy group.The control group took oral paroxetine tablets for treatment,and the observation group received additional acupuncture treatment 3 times weekly.Both groups underwent 4-week treatment.Before treatment,after 2-week and 4-week treatment,and 2 weeks after treatment(follow-up),the patients were assessed using the Hamilton depression scale-17-item(HAMD-17),self-rating depression scale(SDS),self-rating anxiety scale(SAS),and traditional Chinese medicine(TCM)pattern element identification scale for depression.The two groups each randomly contributed 25 cases to detect the protein content of brain-derived neurotrophic factor(BDNF)before treatment and after 4-week treatment,and compared with the healthy group. Results:After 2-week treatment,the markedly effective and total effective rates were significantly higher in the observation group than in the control group(P<0.05);after 4-week treatment,the observation group significantly surpassed the control group in comparing the markedly effective rate(P<0.05).After 2 and 4 weeks of treatment and at the follow-up,the HAMD-17 total score and sleep disorder factor score were lower in the observation group than in the control group(P<0.05);the anxiety-somatic score was lower in the observation group than in the control group after 2-week treatment(P<0.05).After 2 and 4 weeks of treatment and at the follow-up,the observation group was lower than the control group in comparing the scores of SDS,SAS,and TCM pattern element identification scale for depression(P<0.05).After 4-week treatment,the observation group had an increased serum BDNF protein content,higher than that in the control group(P<0.05)and had no significant difference compared to the healthy group(P>0.05). Conclusion:Compared to the use of oral paroxetine alone,acupuncture plus paroxetine can produce more significant efficacy in treating mild-to-moderate depression and act faster in improving sleep disorder and anxiety-somatic symptoms;increasing the serum BDNF protein content may be a part of the mechanism underlying its antidepressant actions.