Objective To investigate the correlation of elderly knee osteoarthritis with bone marrow edema and osteoprotegerin, DKK-1 (dickkopf-1), sclerostin. Methods A total of 100 elderly patients with knee osteoarthritis in Sichuan Province Orthopedic Hospital from September 2017 to December 2018 were selected and divided into bone marrow edema group (50 cases) and non-bone marrow edema group (50 cases). The patients’ basic data, Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scores and Visual Analogue Scale scores were collected. The patients’ serum osteoprotegerin, DKK-1, sclerostin, C-reactive protein, and erythrocyte sedimentation rate were tested, and the differences between the two groups were compared. The correlation of the detection indicators and bone marrow edema and its clinical indicators was explored. Results There was no significant difference in age, gender, course of disease, C-reactive protein and erythrocyte sedimentation rate between the two groups (P>0.05). WOMAC scores (76.1±5.4 vs. 67.5±6.6), Visual Analogue Scale scores (8.4±1.1 vs. 5.5±0.9), proportion of synovitis (84.0% vs. 52.0%), osteoprotegerin [(1.3±1.1) vs. (0.6±0.5) μg/L], DKK-1 [(18.4±16.9) vs. (6.9±6.0) μg/L] and sclerostin [(147.3±119.4) vs. (99.7±70.7) pg/mL] in the bone marrow edema group were higher than those in the non-bone marrow edema group (P<0.05). There was no statistically significant correlation of the bone marrow edema volume score and degree score and serum osteoprotegerin of patients in the bone marrow edema group (P>0.05). The bone marrow edema volume score and degree score of patients in the bone marrow edema group were positively correlated with serum DKK-1 (volume score rs=0.464, P=0.001; degree score rs=0.379, P=0.007) and sclerostin (volume score rs=0.316, P=0.025; degree score rs=0.461, P=0.003). Conclusion In elderly patients with knee osteoarthritis and bone marrow edema, the local bone metabolism indicators of osteoprotegerin, DKK-1 and sclerostin are up-regulated, especially DKK-1 and sclerostin are related to the severity of bone marrow edema.