Objective To observe the expression of c-Myc, RhoA and YAP proteins in the kidney and to determine their relationship with tubulointerstitial fibrosis in adenine-induced chronic kidney disease. Methods Thirty rats were randomly divided into a control (Con) group and a CKD (adenine-induced chronic kidney disease rat model) group. Rats were euthanized at weeks 4, 6, and 8. The levels of renal function and 24-hour urine protein in the two groups were determined. Hematoxylin & Eosin (HE) staining was used to observe pathological changes in the kidney and to score the degree of renal interstitial injury. Interstitial fibers of renal tubules were observed by Sirius red staining and the degree of fibrosis was determined. Immunohistochemical staining was used to observe the expression of c-Myc, RhoA and YAP proteins in renal tissue. RT-PCR was used to detect the mRNA levels of c-Myc, RhoA, YAP, Vimentin, Col1, and α- SMA. The relationship between the expression of c-Myc, RhoA, and YAP and renal tubular interstitial fibrosis was analyzed. Results Compared with the Con group, the blood urea nitrogen(BUN), serum creatinine( Scr), cystatin C (Cysc), and the 24-hour urine protein level of the CKD group were significantly increased ( (P< 0. 05). HE staining showed that the renal tubules were significantly expanded, and Sirius red staining showed a significant increase in collagen fibers. Immunohistochemistry showed that the expression of c-Myc, RhoA, YAP, Col1, and αSMA proteins in the CKD group was significantly higher than that in the Con group (P<0. 05). The levels of c-Myc, RhoA, and YAP mRNA were positively correlated with Col1 mRNA (r= 0. 927 P= 0. 001; r= 0. 988 P= 0. 001;r= 0. 745 P= 0. 013, respectively) and α SMA mRNA levels (r= 0. 988; P= 0. 001; r= 0. 818; P= 0. 004;r= 0. 770; P= 0. 009, respectively). Additionally, a significant positive correlation was found between c-Myc and RhoA mRNA (r= 0. 721 P= 0. 019), and RhoA and YAP mRNA (r=0. 661 P= 0. 038). Conclusions In a rat adenine-induced renal tubular interstitial fibrosis model, c-Myc, RhoA and YAP proteins were highly expressed and were closely related to the degree of renal tubular interstitial fibrosis.