Inclusion Criteria:

1. Patients of either sex aged 18 to 80 years inclusive, who with cancers of all type.

2. Patients with moderate to severe cancer pain, whose pain intensity NRS ≥4.

3. Patients who can understand and are able to complete NRS and BPI assessment.

4. Patients who have given written informed consent to participate in the study.

Exclusion Criteria:

1. Patients who are pregnant, or lactating.

2. Patients who are unable to manage their pain effectively with opioids.

3. Patient who need ≥120mg morphine or equivalent for treatment of pain at time of study
entry;

4. Patients who are receiving chemotherapy, or still under the responsive period of
chemotherapy (patients who are at the interval period of chemotherapy can be enrolled
into study. That is to say, patients who completed chemotherapy for more than 2 weeks
can enrolled, or patients has completed chemotherapy for at least one week could be
enrolled at the discretion of the investigator).

5. Patients who have received radio-therapy for bony metastasis, patients receiving
radiotherapy within the 4 week period before study entry (patient receiving
radiotherapy for area other than pain area can be enrolled) , or patients who were
scheduled to receive radiotherapy for pain area during study period.

6. Patients are receiving or should receive anti-convulsion drugs/anti- depression drugs
considered by investigator for the treatment of neuropathy pain. Patients are
receiving or should receive any analgesic other than study medicine, which including
NSAIDs.

7. Patients with other unstable disease, or with dysfunction of important organ.

8. Patients with an ongoing infection, abscess or fever.

9. Patient with serious abnormal liver/ renal function (ALT/AST/creatinine/urea
nitrogen) which is higher than 3 times of upper limit;

10. Paralytic or mechanical ileus;

11. Persistent asthma, chronic obstructive diseases, and cor pulmonary;

12. Intracranial neoplasms, and intracranial hypertension with central respiratory
depression risk.

13. Monoamine oxidase inhibitors (MAOIs) or same type drugs have been administered in
last 2 weeks;

14. Patients who are currently taking active treatment for epilepsy or arrhythmias.

15. Patients with known sensitivity or record of specific or allergic reaction to
oxycodone or morphine.

16. Patients excluded by the contra-indications, adverse drug reaction (ADRs) and drug
interactions of oxycodone or morphine as detailed in the data sheet, summary of
product characteristics or investigator's brochure.

17. Patients with a history of drug or alcohol abuse.

18. Patients who participated in another clinical research study involving a new chemical
entity within one month prior to study entry.

19. Patients whose concomitant medication is likely to be changed within the study
period, with the exception of treatment for opioid side effects.

20. Patients who, in the opinion of the investigator, are unsuitable to participate in
the study for any other reason not mentioned in the inclusion and exclusion criteria.