This research was conducted from January until May 2015 at Pangkalan Panduk Village Kerumutan Subdistrict of Pelalawan Regency of Riau Province. The research aimed to determine the differences value pH, C-organik, KTK, N-total, P-total, and K-total at 0-50 cm, samples from forest peatlands, oil palm plantations at the age of 7 years and industrial forest plantations Acacia crassicarpa at the age of 6 years. The results showed an increase in pH by 0.03 % from peat forests into oil palm plantations and increased pH also occurs in peat forests into industrial forest by 0.96 %; an increase KTK of peat forests into oil palm plantations amounted to 22.62 mg/100g and peat forests into plantations amounting to 113.87 mg/100g; P-total increased from peat forests into oil palm plantations amounted to 22.62 mg/100g and peat forests into plantations also increased by 12.74 mg/100g; K-total increased from peat forests into oil palm plantations of 2.73 mg/100g and peat forests into plantations by also increased by 12.31 mg/100g. For C-organic chemical character changes occur perbedan where a decline of peat forests into oil palm plantations amounted to 11.15 % and an increase of C- organic peat forests into plantations by 0.05 % . Neither the N - total increased from peat forests into oil palm plantations of 0.51 % and a decline of peat forests into plantations by 0.31 %. We conclude changes in the chemical character of peat for all parameters measure were influenced by the changes in secondary forest peatland into oil palm plantations age of 7 years and plantation forests Acacia crassicarpa age 6 years.