Further analysis of a National Schizophrenia Fellowship study also indicates that figures for young people with severe mental illness are the highest ever recorded.
The charity says the finding flies in the face of the common misconception that schizophrenics are mad and dangerous middle-aged men.
The organisation fears mentally-ill youngsters go undiagnosed because their symptoms are attributed to the hormonal changes and "phases" of adolesence.
A spokeswoman said: "Adolescence is the only age group where suicides are rising nationally.
"Despite this, there appear to be cases of misdiagnosis where symptoms of schizophrenia are interpreted as part and parcel of the traumas of adolescence.
To read about how one teenager developed schizophrenia, click here.
"What we hope is that this new statistic will also demonstrate that people with schizophrenia are generally only dangerous to themselves."
The charity's findings are being published to coincide with an LWT programme Up Close Late: Life Hurts, due to go out on ITV at midnight on Friday.
Access to appropriate support
Cliff Prior, of the National Schizophrenia Fellowship said: "The experience of young adulthood can be very stressful, with many life-events taking place at this time.
"These are often cited by young adults as the 'trigger' of a mental health problem.
"People with a severe mental illness need access to appropriate support services when they require it.
"The National Schizophrenia Fellowship hopes the programme will go a long way to helping people understand this urgent need.
"We know that people who receive proper care and treatment at the earliest opportunity have the best outcomes. However, in teenage years, schizophrenia is often misdiagnosed."